Not received a reply to your Freedom of Information Request or you are not satisfied with it?

You can make a complaint if the company does not respond in the time limit stated by law (28 days), or responds inappropriately, to the Information Commissioners Office and they will look at your request to determine how this should be progressed. This applies to both SARs and FOIRs.

https://ico.org.uk/for-organisations/guide-to-freedom-of-information/