If you have a specific grievance about a financial institution, there are several steps to follow in order to have it addressed:
Call the company to find out where to direct your complaint and then submit it, preferably in writing. The BMA requires companies to have a formal complaints procedure in place, including logging, and ensure they are dealt with promptly; this is also a requirement in the market Codes. The Authority has the power to review the complaints log as part of our supervision.
Firms should keep you advised of how they are dealing with your issue; tell you how and when it will be resolved; or clearly explain why it cannot be addressed.
If you're not satisfied with how your issue was addressed by the company, you can contact the Department of Consumer Affairs. They can look at disputes related to customer service issues for specific institutions on an individual, case-by-case basis, and contact the company to see how the issue can be resolved.
Ultimately, if the issue is still not resolved to your satisfaction under steps 1 and 2 above, you can consult a lawyer and seek to take the matter to Court.