Refund

I bought phone covers for my kids and after noticing the covers where wrong/oversized I logged a return and returned the covers unopened and in thier original delivered packages . These where inspected and accepted . After approving my return, they only credited my account half the order value and want to send back the other cover. Weeks later i am still explaining to them both these are from one order. But they rejected my return and don't want to refund my account the other half of the order. MRRN-479P4-GP89