Which app is it? How did you input the provider info initially?

Give him your new MAC address? If you’ve paid for it I don’t see the issue in you changing your TV. They’ll remove the old MAC address from the system and replace it with your new one.

You can snoop the network of your tv and try to extract all urls it is accessing:

https://www.vanimpe.eu/2013/12/12/analyze-network-traffic-tv/