HUAWEI-B525s-23a router and it keeps blocking internet connectivity

Hi there

I have a HUAWEI-B525s-23a router and it keeps blocking internet connectivity comming up with its own SSL certificate and saying invalid. Certifiucate is valid until 2024 , This seems to be somthing to do with the web filtering on the router and the only was to resolve the issue is to rest the router.

I have tried turning of the Firewall but the issue remains without reseting the router?

It says the firmware is up to date and it is using;

Hardware version: WL1B520FM

Software version: 11.236.01.00.1217

Web UI version: 21.100.31.00.03

 is it posable to repair the firmware if so how?

Any advice

Thanks

Roy