@Marco Di Sazio - It is possible to delete a paid team without first cancelling a subscription - this leads to no access to a paid plan, but your continuing to be billed:

Frequently asked questions

1. Will my subscription tied to my team be terminated upon deletion of the team?
   - To make sure that there will be no additional charges, please cancel your subscription in Billing settings: use this guide.

https://help.miro.com/hc/en-us/articles/360017571334-How-to-delete-a-team#Frequently_asked_questions

I will convert your post into a support ticket - you should receive an email notification. You can check the ticket at any time if you:

1. Go to https://help.miro.com/
2. Click “Sign in”
3. Then click on your name → My activities