<prompt> Human: Brief background: I share one bank account and one credit card with ex to split childrens expenses. We put an amount into joint account each month and use it to pay off joint card, which is used to pay for kids expenses.Recently Ive come to suspect that ex is over-buying for kids, returning items and using the store credit on items for ex.Is there anyway I can prevent returns on the card from being used for store credit?  <response>: Recently Ive come to suspect that ex is over-buying for kids, returning items and using the store credit on items for ex.If you suspect they are stealing money from you, the first thing id do is not have joint accounts with them. 