Hello,
Thank you for reaching out!
If the router has a SIM card inserted, SMS commands are on by default.
Since these issues seem to be related to HTTP/HTTPS access, then an SMS command webon can be used. Exact instructions on how to use SMS commands are explained in the linked article. This function is on by default.
As for the firewall rules themselves, UCI commands can also be used for a more advanced configuration.
Hope this helped!
Best regards,
DaumantasG