If you can't untie through Momo, you can try to open Alipay. There is a mine in the lower right corner and a setting in the upper right corner.

There are payment settings in it After clicking in, there will be a secret-free payment with automatic deduction. I'll see the agreement you signed when I go in. Click on the agreement and continue to pull down. There is a delete button. Click Delete, and you will be prompted to delete and terminate the contract. Click OK.