Yousician Subscription Charged $10 Without Consent — Requesting Refund From Google

I discovered that $10 was deducted from my account for a subscription to an app called Yousician through Google, even though I was not aware of having any membership and did not give my permission or consent. I want an explanation for how this money was withdrawn from my account without my knowledge or authorization, and I am requesting a full refund.

If a refund is not issued, I am prepared to take legal action against Yousician or Google if necessary.