Reviewer unable to download file (OJS

Some of the reviewer unable to download the file. If he was clicking to download then page not responding. 500 error was showing.

We have checked error log bellow mentioned error log was generated:-

[22-Jun-2022 16:44:07 Asia/Kolkata] PHP Fatal error: Uncaught Error: Call to a member function getLocalizedName() on null in /EPUB/ojs/lib/pkp/controllers/api/file/
Stack trace:
#0 /EPUB/ojs/lib/pkp/classes/core/ FileApiHandler->downloadFile()
#1 /EPUB/ojs/lib/pkp/classes/core/ PKPRouter->_authorizeInitializeAndCallRequest()
#2 /EPUB/ojs/lib/pkp/classes/core/ PKPComponentRouter->route()
#3 /EPUB/ojs/lib/pkp/classes/core/ Dispatcher->dispatch()
#4 /EPUB/ojs/index.php(68): PKPApplication->execute()
#5 {main}
thrown in /EPUB/ojs/lib/pkp/controllers/api/file/ on line 109