Barclays Credit Card Complaint

Barclays Credit card department,

Billing statement New Jersey

I have paid my account balance to barclay card ( apple rewards ) in full each statement. Each time I went online to access my account, the balance did not - out and I had a balance due. I have as result overpaid my account by $540.00. I have requested a refund of this amount from the card holder however, I am reporting this because their systems are not accurately crediting payments.