Note that as this process may temporarily interrupt your internet connection and phone service, we recommend doing this in an off-peak period or outside of business hours.
Learn more about SIP ALG in our knowledge base article here: SIP ALG
Disabling SIP ALG
From the menu, choose Administration > Management
Find the ALG section, then set SIP to Disabled and save your settings. If you're prompted to restart your router, please do so.