Page can't be displayed

I have a big website with many plugins, but a robust server from contabo.
Many times when I try to save contents or settings inside WordPress I get “Page can’t be displayed” after long run.
Is that related to PHP or some setting in OpenLiteSpeed or else?!

Maybe you are hitting the php memory limit?
Go to your PHP settings, change 64/128MB to 256MB and restart PHP, should help.

@tmoore that was the first thing I changed after cyberpanel installation before migrating my site.
memory_limit = 4096M

@tmoore any feedback on this issue, please?!