Hello,
1) Our user does not have access to theme options, themes or plugins https://prnt.sc/1x3qds8
Please, change the permissions of our user to allow us to check the mentioned things.
2) I don’t see Ajax error but I see js error in console https://prnt.sc/1x3qiz2 So, provide us also with the FTP access to your site to check it in more detail.
Regards