AMC+ charging me when i have subscription

If you are subscribed directly with the provider then you would need to use their app, if it supports Apple's TV app then make sure it is connected. If you subscribed to the Apple TV channel version then you can consult Apple support.

It's offering the option of buying the episode, not actually trying to charge you.

If you have a subscription to AMC+, then scroll down to the "How to Watch" section and it should offer the AMC+ option.

If you subscribed directly in the AMC+ app, then you need to find and watch the episode directly through the App.

Yeah, unfortunately that will be the case for many services where there are existing contracts in place for the content. Hopefully once those run out AMC may just retain the rights exclusively for their service.

If there are no other options in How to Watch besides Apple TV options, then its not yet available on other platforms.

As mentioned it may take a bit to get released on AMC+ directly.

It would be dependent on the service provider and what they have license to for a particular location. If you were able to get a refund that's great. Have a nice day.