Google play billing using old account info

[BittyPanda]

So I divorced last year and got onto a different phone plan. I still play a few games that I played while on the old account and made purchases using the Bill My Verizon Account option. Now when I try to make purchases using this option, it's still asking for my ex's old Verizon account and wants that password to verify the purchase, but it bills my new Verizon account. How do I get Google play to ask for MY current Verizon credentials to verify the purchase instead of asking for my ex's cause when he changes the password I'm going the be screwed.