403 Forbidden Access Error

Hello,

I am building a website for a client and one of the plugins I use is Ultimate Member to manage user sign ups and email notifications. Initially, I had built the website within my hosting on the domain name https://reports.25thhour.co.za as my client was busy setting up a test environment for me within their server.

Everything worked perfectly on my domain name, when their test environment was ready I performed a migration and the ultimate member plugin now does not allow me to enable, tweak and save email templates and gives me a 403 forbidden access error page.

I tried the following solutions:
1. Disabled mod security
2. Disabled hotlink protection
3. Tweaked file permissions in cPanel following the suggestions here: https://www.wpbeginner.com/wp-tutorials/how-to-fix-the-403-forbidden-error-in-wordpress/
4. Disabled all plugins and left UM running alone
5. Changed the theme to a different theme
6. Rebuilt the website in the new test environment
7. Generated a new htaccess file and disabled the old one (I eventually deleted the old htaccess file too)

None of the aforementioned solutions worked. All other plugins I tried after that worked but lack the features I need as they are all in UM.

What could be the problem?

Regards,
Abo

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