I assume here that you have the Pay to Join option on.
The problem probably lies with your settings in PayPal. The last time I looked at the Pay to Join feature for a site, it had issues and they finally took it down and went back to the free to join with promotional/standard memberships.
What you see in Cheetah's backend is the settings that Cheetah sees. It is possible you have more than one version of PHP installed and you see it differently when you go to the server. By the way, Cheetah can use PHP 7.4 so I recommend you use that version as it is faster than 5.6. Be sure the op code cache is turned on in PHP as well for improved performance.