Why am I being charged for Apple TV+ with Apple Music student subscription?

I’m an Apple Music student subscriber. When I opened my Apple TV+ app on my TV it asked me to start a subscription. I’ve been getting free access to Apple TV+ ever since I started my Apple Music student subscription. Why am I going to get charged for Apple TV+? I just renewed my Apple Music subscription via Unydays.

[Re-Titled by Moderator]