Why can't I forward to Firewall?
If you can’t set up forwarding to Firewall, there might be a few things going on that are preventing you from forwarding your calls.
Firewall is currently only available with AT&T, Verizon, T-Mobile, and Sprint. If you have another carrier, you won’t be able to set up forwarding to Firewall. Similarly, Firewall is only compatible on iPhones with iOS 11 or newer. If you're interested in hearing about updates on Firewall for Android devices, you can sign up for email updates.
Firewall is a robocall blocker app that forwards your calls to a Firewall number and then screens all inbound calls. If you have a prepaid phone plan that doesn’t allow call forwarding, you will not be able to use the app. Similarly, using other VoIP services or calling apps might impede forwarding.
Occasionally on unlocked devices, there will be an IMEI mismatch on your carrier's end that will prevent call forwarding. When you go through the Firewall setup flow, you will not be able to set up call forwarding.
Since this is an issue on your carrier's end, the only fix is for you to reach out to your carrier's support team and tell them that you think you have an IMEI mismatch. You'll need to find your devices' IMEI which you can do by going to your iPhone's Settings > General > About and then give your device's IMEI to their customer support. Your carrier should be able to reset your IMEI and then you should be able to set up call forwarding to Firewall.
You can always reach out to firstname.lastname@example.org if you have any other questions or need help setting up Firewall!