Additional features, settings, or issues not covered by specific Microsoft Teams Free categories
Greetings!
This is Tin, I'll do my best to help. May I know where did you purchase your MS Teams subscription? If from MS Store, you can cancel it from https://account.microsoft.com/services and sign in the account that you've used to purchase. But if you have purchased it from Apple Store, Google Play Store or any 3rd party, it would be best to reach them regarding the cancellation.
In case you've purchased it from MS Store and you're still unable to cancel it, please try to use different browser or device and check if its the same. If yes, it would be best to reach MS Accounts & Billing Support:
Kindly open this link: https://support.microsoft.com/contactus/
Ensure that your MS Account has been signed in
Type "Chat with an agent" and hit Enter.
Please click the "Contact support"
Please select the "Products and services"
Please follow the prompts to connect with a live agent.
You may also choose the "Call me back" option if you prefer to receive a call.
Once you're connected to the Live Agent, please let them know about your issue so they could check your account and address your concern.
Thank you,
Christine