PHP update and cause an error

Transport template - the server updated to PHP 7.3 and
It updated and mess up the website with an error
So I put it back to PHP 5.6
 This was the warning
Warning: session_start(): Failed to read session data: user (path: /tmp) in /home1/fernkloo/public_html/libraries/joomla/session/handler/native.php on line 260
Error: Failed to start application: Failed to start the session

website - www.fernkloof.org.za/  

Hello,

I suppose you are using Joomla 3. Our templates are compatible with PHP 7. However, it's possible that you have old template files. In this case, you need to re-download the template files (from our new portal) and re-upload the template files using FTP.

Also, it's possible that this issue is caused by another extension you are using, not our template. Please check all your extensions on this website if they are compatible with PHP 7.

Regards,
Milos

I cannot fix this - we removed all plugins not needed
move back tp php5.6 - work ok for a day or 2 and than
Warning: session_start(): Failed to read session data: user (path: /tmp) in /home1/fernkloo/public_html/libraries/joomla/session/handler/native.php on line 260
again

Hello,

You should use PHP 7 because PHP 5.6 is outdated and both Joomla 3 and (especially) Joomla 4 are not fully optimized for it.

Your issues are related to your hosting. Please consult your web hosting provider, show them the errors and let them help you with the proper configuration of /tmp folder. Only the server administrator can solve this issue.

You can try the same template on different hosting.

Regards,
Milos