Hello again @ramil1984 ,
It might be an issue caused by a plugin or your theme.
I recommend installing this plugin: https://www.ads-software.com/plugins/health-check/
After you install and activate the above plugin it has a Troubleshooting mode which allows you to have a vanilla WordPress session, where all plugins are disabled, and a default theme is used, but only for your user – your visitors will still see the normal website.
Go to its troubleshoot mode and only activate Modula and see if it works correctly with a default WordPress theme (Twenty Nineteen for example) and no other plugins.
Please let me know how it goes and what you find!
If it didn’t work, please send us more details from Testimonials because we really want to help you, we just need all the settings you have in this plugin!I would prefer more screenshots!
Thank you for your understanding!
All the best,
Marian