SQLSTATE[08004] [1040] Too many connections Error

Dear Team,

We had the fatal error below when we upgraded our system to 3.3.0.17 PHP 8.0
This error is repeating it self which make log file so large. I looked the forum to see if someone faced the same issue but got nothing
your help is highly appreciated.
-Salam

[27-May-2024 09:25:40 UTC] PHP Fatal error:  Uncaught PDOException: SQLSTATE[08004] [1040] Too many connections in /***/***public_html/lib/pkp/lib/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOConnection.php:38
Stack trace:
#0 /***/***public_html/lib/pkp/lib/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOConnection.php(38): PDO->__construct('mysql:host=loca...', '*********", '*********", Array)
#1 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(67): Doctrine\DBAL\Driver\PDOConnection->__construct('mysql:host=loca...', '*********", '*********", Array)
#2 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(46): Illuminate\Database\Connectors\Connector->createPdoConnection('mysql:host=loca...', '*********", '*********", Array)
#3 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/MySqlConnector.php(24): Illuminate\Database\Connectors\Connector->createConnection('mysql:host=loca...', Array, Array)
#4 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/ConnectionFactory.php(184): Illuminate\Database\Connectors\MySqlConnector->connect(Array)
#5 [internal function]: Illuminate\Database\Connectors\ConnectionFactory->Illuminate\Database\Connectors\{closure}()
#6 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(926): call_user_func(Object(Closure))
#7 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(961): Illuminate\Database\Connection->getPdo()
#8 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(405): Illuminate\Database\Connection->getReadPdo()
#9 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(360): Illuminate\Database\Connection->getPdoForSelect(true)
#10 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(664): Illuminate\Database\Connection->Illuminate\Database\{closure}(Object(Illuminate\Database\Query\Expression), Array)
#11 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(631): Illuminate\Database\Connection->runQueryCallback(Object(Illuminate\Database\Query\Expression), Array, Object(Closure))
#12 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(373): Illuminate\Database\Connection->run(Object(Illuminate\Database\Query\Expression), Array, Object(Closure))
#13 [internal function]: Illuminate\Database\Connection->cursor(Object(Illuminate\Database\Query\Expression), Array)
#14 /***/***public_html/lib/pkp/classes/session/SessionDAO.inc.php(37): Generator->current()
#15 /***/***public_html/lib/pkp/classes/session/SessionManager.inc.php(170): SessionDAO->getSession('268f07f13ea1f8d...')
#16 [internal function]: SessionManager->read('268f07f13ea1f8d...')
#17 /***/***public_html/lib/pkp/classes/session/SessionManager.inc.php(60): session_start()
#18 /***/***public_html/lib/pkp/classes/session/SessionManager.inc.php(131): SessionManager->__construct(Object(SessionDAO), Object(Request))
#19 /***/***public_html/lib/pkp/classes/i18n/PKPLocale.inc.php(131): SessionManager::getManager()
#20 /***/***public_html/lib/pkp/classes/i18n/PKPLocale.inc.php(290): PKPLocale::getLocale()
#21 /***/***public_html/lib/pkp/classes/core/Dispatcher.inc.php(116): PKPLocale::initialize(Object(Request))
#22 /***/***public_html/lib/pkp/classes/core/PKPApplication.inc.php(360): Dispatcher->dispatch(Object(Request))
#23 /***/***public_html/index.php(68): PKPApplication->execute()
#24 {main}

Next Doctrine\DBAL\Driver\PDO\Exception: SQLSTATE[08004] [1040] Too many connections in /***/***public_html/lib/pkp/lib/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDO/Exception.php:18
Stack trace:
#0 /***/***public_html/lib/pkp/lib/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOConnection.php(42): Doctrine\DBAL\Driver\PDO\Exception::new(Object(PDOException))
#1 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(67): Doctrine\DBAL\Driver\PDOConnection->__construct('mysql:host=loca...', '*********", '*********", Array)
#2 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(46): Illuminate\Database\Connectors\Connector->createPdoConnection('mysql:host=loca...', '*********", '*********", Array)
#3 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/MySqlConnector.php(24): Illuminate\Database\Connectors\Connector->createConnection('mysql:host=loca...', Array, Array)
#4 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/ConnectionFactory.php(184): Illuminate\Database\Connectors\MySqlConnector->connect(Array)
#5 [internal function]: Illuminate\Database\Connectors\ConnectionFactory->Illuminate\Database\Connectors\{closure}()
#6 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(926): call_user_func(Object(Closure))
#7 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(961): Illuminate\Database\Connection->getPdo()
#8 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(405): Illuminate\Database\Connection->getReadPdo()
#9 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(360): Illuminate\Database\Connection->getPdoForSelect(true)
#10 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(664): Illuminate\Database\Connection->Illuminate\Database\{closure}(Object(Illuminate\Database\Query\Expression), Array)
#11 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(631): Illuminate\Database\Connection->runQueryCallback(Object(Illuminate\Database\Query\Expression), Array, Object(Closure))
#12 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(373): Illuminate\Database\Connection->run(Object(Illuminate\Database\Query\Expression), Array, Object(Closure))
#13 [internal function]: Illuminate\Database\Connection->cursor(Object(Illuminate\Database\Query\Expression), Array)
#14 /***/***public_html/lib/pkp/classes/session/SessionDAO.inc.php(37): Generator->current()
#15 /***/***public_html/lib/pkp/classes/session/SessionManager.inc.php(170): SessionDAO->getSession('268f07f13ea1f8d...')
#16 [internal function]: SessionManager->read('268f07f13ea1f8d...')
#17 /***/***public_html/lib/pkp/classes/session/SessionManager.inc.php(60): session_start()
#18 /***/***public_html/lib/pkp/classes/session/SessionManager.inc.php(131): SessionManager->__construct(Object(SessionDAO), Object(Request))
#19 /***/***public_html/lib/pkp/classes/i18n/PKPLocale.inc.php(131): SessionManager::getManager()
#20 /***/***public_html/lib/pkp/classes/i18n/PKPLocale.inc.php(290): PKPLocale::getLocale()
#21 /***/***public_html/lib/pkp/classes/core/Dispatcher.inc.php(116): PKPLocale::initialize(Object(Request))
#22 /***/***public_html/lib/pkp/classes/core/PKPApplication.inc.php(360): Dispatcher->dispatch(Object(Request))
#23 /***/***public_html/index.php(68): PKPApplication->execute()
#24 {main}

Next Illuminate\Database\QueryException: SQLSTATE[08004] [1040] Too many connections (SQL: SELECT * FROM sessions WHERE session_id = 268f07f13ea1f8d27fbb6949bad5a082) in /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php:671
Stack trace:
#0 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(631): Illuminate\Database\Connection->runQueryCallback(Object(Illuminate\Database\Query\Expression), Array, Object(Closure))
#1 /***/***public_html/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(373): Illuminate\Database\Connection->run(Object(Illuminate\Database\Query\Expression), Array, Object(Closure))
#2 [internal function]: Illuminate\Database\Connection->cursor(Object(Illuminate\Database\Query\Expression), Array)
#3 /***/***public_html/lib/pkp/classes/session/SessionDAO.inc.php(37): Generator->current()
#4 /***/***public_html/lib/pkp/classes/session/SessionManager.inc.php(170): SessionDAO->getSession('268f07f13ea1f8d...')
#5 [internal function]: SessionManager->read('268f07f13ea1f8d...')
#6 /***/***public_html/lib/pkp/classes/session/SessionManager.inc.php(60): session_start()
#7 /***/***public_html/lib/pkp/classes/session/SessionManager.inc.php(131): SessionManager->__construct(Object(SessionDAO), Object(Request))
#8 /***/***public_html/lib/pkp/classes/i18n/PKPLocale.inc.php(131): SessionManager::getManager()
#9 /***/***public_html/lib/pkp/classes/i18n/PKPLocale.inc.php(290): PKPLocale::getLocale()
#10 /***/***public_html/lib/pkp/classes/core/Dispatcher.inc.php(116): PKPLocale::initialize(Object(Request))
#11 /***/***public_html/lib/pkp/classes/core/PKPApplication.inc.php(360): Dispatcher->dispatch(Object(Request))
#12 /***/***public_html/index.php(68): PKPApplication->execute()
#13 {main}