Last week we migrated to new server from Cent OS 6 to7 along with PHP7.4 and Maria DB.

We did all test and everything was working fine for 5-6 days.

Last night we tweak MySQL tuneup to optimize and today morning 1 user complain that she cannot post. Then second and then third and so one.

Few complaining about cant post new topics, others complaining cant edit topic.

I can post new topic but cannot edit as an admin even.

Please help. Thanks in advance.

Are there any logged errors in your server log, php error log or IPS system log?

There are only these two system log from today and none in error log

Support help us to identify that we need to switch off mod_security on our new cpanel server and then we could post again.