Why i am getting this error

https://ibb.co/xg2rfkv

Hi there,

the first things to check is:

1. You're logged in as an Administrator.
2. Your browser hasn't stored a cookie that is confusing 'who' you are - clear caches and cookies.

If its not one of those simple reasons then it can be one of may issues - detailed guide here:

https://kinsta.com/knowledgebase/sorry-you-are-not-allowed-to-access-this-page-error-in-wordpress/

I would begin with disabling plugins to see if there is a conflict

I am having errors in the theme itself

Can you please check what is the error with the theme? For now, I changed the theme to a 2021 theme so that website can run.

Have you resolved this?

I logged in using the credential provided and didn't see the issue.

Is there a specific page where you are seeing this?

Yes it is solved after i turned on wp_debug

Glad to hear :)