UMB Bank Credit Card Complaint

UMB Bank Credit card department,

Balance transfer Kansas

Quicktrip has offered gas station card through UMB Bank. I held a card which was paid in good standing. They switched provders to - - - - - earlier this year. I changed where I am sending payments and monthly statements provided by - - - - - show my account is laid. But I am now receiving collections letters from UMB Bank saying I owe on my Quiktrip account. What gives?! I have paid every statement I 've gotten!