Gootle tries to prevent cancelling/unsubscribing. It seems that they use backward evolution techniques.
1. Log in to your Google email account.
2. Go to Billing (you will find it in the square dots menu on right hand side of screen)
3. On Billing page on the right hand side you will find three vertical dots. Click it to cut the iron chain.
I don’t know how much LSD one would need to consume to invent three vertical dots as intuitive icon for cancelling subscription.