Barclays PLC Credit Card Complaint

Barclays PLC Credit card department,

Credit card protection / Debt protection Maryland

I have a credit card with barclaycard us. I informed barclay of an unauthorized ( refund ) charge on my account by a merchant who send an email confirmation stating that this charge was refunded and should be refunded. I provided the refund confirmation email to barclay over a year ago to no avail. I have been back and forth with barclay for an entire year. The provided a provisional credit and then reverse the credit with no explanation. I last spoke with - a customer representative of barclay on -/-/- who confirmed that all the documents was received for the credit and she send an email to that department for processing. She informed me I will hear from barclay in 72 hours and no one contact me. I called again on -/-/- and spoke with - again and she again said someone will contact me when the charge is reverse. I did not receive any calls from anyone. I have received interest charges on this account for over a year and I am asking for the reversal of the charge and the all interest charges for this transaction over the entire year plus. The amount is $210.00 and the company name is - -. - has not respond and refuse to response since communication in -.