Wordpress not saving changes - php max_input_vars issue?

hello, i'm having issues with a hosted website.
the website was developed locally and then uploaded to the server. It is wordpress based and use a page builder.
Everything is fine but when i try to change something inside a page, in the builder part... it doesn't save the changes.

the theme support says it depends on the server, and the php max_input_vars should be the problem. Actually if the change is small it works, but it doesn't when it's a bigger change. i put the max_input_vars to 25000 but i still get the error.

Any hint on how to fix? thanks

I suspect that you'll need to exclude a mod_sec rule (if indeed you have it activated!), though will open a door for parameter abuse.

I agree with ejsolutions, it's very likely that mod_sec will cause issues with page builders or even WordPress itself, even though it has a default exclusion list.

Does the page refresh but doesn't save or just loads forever when you hit the save button? Also maybe take a look at apache's error logs to see what the problem is exactly.

Mod_sec log will flag the access IP as a violation and display the rule number that triggered it.

thanks i disabled it for the time of the changes and then reenabled, it worked fine

thanks ejsolutions

thanks i disabled it for the time of the changes and then reenabled, it worked fine

A valid way of doing this, for better protection - if you remember the next time.
It's what I'd do, given the amount of hack attempts against Wordpress - be sure to add Wordfence!
(You can disable a rule for a specific website, so as not to compromise the whole server.)