Cannot Make Changes

Hello. I do not know what the problem is but I cannot add or change users, groups or modules. I can create content though. 

Everything was working fine. I started trying to improve the security on my site. I was adding things like content security policy and HSTS and that all seemed fine. Mostly I was changing the structure of the relations between things, really just setting up the functionality. There hasn’t been any content or users.

At that point (a few days ago) my site was no longer accessible. I got errors saying the SSL certificate expired even though I was still paid up. So I contacted my host and they renewed it. Things were back up within minutes. 

Then I started noticing the problem of not being able to add more groups or users. I don’t know if it’s something I did or if it has to do with SSL. 

I then deleted my site and made a new database and reinstalled drupal. Again, everything is configured perfectly it appears but the problem persists. So I think it’s not a module thing. Perhaps a database or SSL thing.

Any ideas would be greatly appreciated. Thanks.

Drupal version: 


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