I’m being charged for an app I don’t have

I downloaded the Filescanner app in 2015 (?), not knowing there was an annual renewal. Upon realizing this, I unsubscribed from it. Suddenly, a charge shows up in my bank account this morning. The app isn’t in my phone or even in my subscription history. I’m living in a new state, new bank account, new phone.

I have gone gone round and round in the settings trying to eliminate this problem, but I can’t even find the app’s info.

PLEASE HELP! There must be some recourse to resolve this issue!