For Essex. Claims form. It states 90% of claims are rejected. I wonder why.
They say - Most roads and pavements in Essex are our responsibility. We have a statutory duty under the Highways Act 1980 to carry out routine safety inspections at varying frequencies to identify any road or pavement in need of repair.
They have a duty! Must be the same for every council. Please make yourselves heard to them. I was told by someone to report by telephone telling them the damage/pothole is dangerous. This lady said all hers have been done after a phone call. I don't know, but it can't hurt.

https://www.essexhighways.org/roads-and-pavements/make-a-claim