Cannot access (blank page) article page after applying SSL certificate

Dear all,
I am still using Ojs 3.1.0.0
We asked the server provider to upgrade hosting package. Initially, the http://jurnalbeta.ac.id was a subdomain of a cpanel with main domain jurnalbeta.com. We asked to use jurnalbeta.ac.id as main domain of the new cpanel. We also asked to apply SSL certificate. After all of these, I could not access the article page e.g. Membangun koneksi matematis siswa dalam pemecahan masalah verbal | Beta: Jurnal Tadris Matematika
Is it related process of upgrading and applying SSL certificate?
I am not able yet to access the error logs
@bozana @anupent @asmecher

Hi @kawahyu,

You’ll definitely need your PHP error log to debug this.

Regards,
Alec Smecher
Public Knowledge Project Team

I found this

[25-May-2018 20:34:42 UTC] ojs2: 404 Not Found
[25-May-2018 20:35:15 UTC] ojs2: 404 Not Found
[25-May-2018 20:35:41 UTC] ojs2: 404 Not Found
[25-May-2018 20:55:43 UTC] ojs2: 404 Not Found
[25-May-2018 21:02:30 UTC] PHP Warning:  phpinfo(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone. in /home/k2542002/public_html/info.php on line 1
[25-May-2018 21:02:37 UTC] PHP Fatal error:  Call to undefined function Symfony\Polyfill\Mbstring\iconv() in /home/k2542002/public_html/plugins/generic/citationStyleLanguage/lib/vendor/symfony/polyfill-mbstring/Mbstring.php on line 154
[25-May-2018 21:02:38 UTC] PHP Warning:  mktime(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone. in /home/k2542002/public_html/lib/pkp/lib/adodb/adodb-time.inc.php on line 1073
[25-May-2018 21:02:40 UTC] PHP Warning:  mktime(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone. in /home/k2542002/public_html/lib/pkp/lib/adodb/adodb-time.inc.php on line 1073

I also found the issue in this thread OJS 3.1 blank index page - #2 by ojsbsb
@ajnyga suggested this and solve the issue

Have you tried to empty the template cache in cache/t_compile?
Does it mean all files in t_compile folder deleted?

Hi @kawahyu,

Try installing the iconv extension in your PHP configuration.

Regards,
Alec Smecher
Public Knowledge Project Team

Dear @asmecher
The server provider is slow response. In my cpanel there is multiPHP INI editor. What should I write in editor mode which refer to /public_html/php.ini?

The server provider has activated it and resolved the problem. Thanks a lot @asmecher