If you reset bridge identifier, or delete the entire cache and try to re-pair the bridge in Homekit it won't allow it. It keeps the same 4 digits number associated with the bridge and Homekit reports an 'Invalid security check or Action not allowed' error. The bridge must first be deleted from Homekit, then re-added with the new identifier, meaning Homekit recognizes is as the same bridge but with some different data therefore showing the invalid security check error.
If you reset bridge identifier, or delete the entire cache and try to re-pair the bridge in Homekit it won't allow it. It keeps the same 4 digits number associated with the bridge and Homekit reports an 'Invalid security check or Action not allowed' error. The bridge must first be deleted from Homekit, then re-added with the new identifier, meaning Homekit recognizes is as the same bridge but with some different data therefore showing the invalid security check error.