I have installed the GP Premium into my WordPress website (on WP network and only 1 website) and i have selected a theme from site library name “Ethos” but when I edit anything and update nothing happened, the content not updated. (Classic and the Gutenberg editor is not installed only the GenerateBlocks)
This is WordPress core function that the theme has no control over, so it must be a WP / Server settings issue.
Check your server error logs to see if any errors are reported after saving changes to the post. This should give you a pointer as to what is going wrong.
I turned off the Generateblocks plugin and then switched from block editor to classic in the settings and network settings. I modified the post and still didn’t save it.
The next step was to turn the Generateblocks plugin back on and then switch to the classic editor inside the editor, so it saved. Unfortunately i don’t see the styles in classic editor.
The fact that your pages still weren’t saving without GenerateBlocks activated shows me that there’s likely something up with your WordPress installation/server. We haven’t had any other reports of similar issues since you’ve mentioned this.
If you create a test site on the same server, is this issue reproducible?