FCA DISP complaints handling rules
Barclays must handle complaints in accordance with the FCA Handbook's DISP (Dispute Resolution: Complaints) rules. They must acknowledge your complaint promptly, keep you updated on progress, and provide a final response within 8 weeks for most complaint types. The final response must clearly explain their decision and your right to refer to the Financial Ombudsman Service.
FCA Handbook DISP 1.6