Finance Department does not respond to escalations for refund queries

Specifically pertaining to resolution of a refund, this review is directed at the finance department. A double order was placed, with one of the orders being returned and the return processed. However, the refund has, since the end of June to date, not reflected on my payment method. I have raised this with Customer Service, call reference ***, with repeated follow ups. Each time I've been told that the query was escalated to the finance department and advised that I would receive feedback. No feedback has been received and daily checks on my account still indicate the refund was not completed.