The best choice is to contact Apple Support and ATT support for expert help. Hardware issues: Failing to forward the incoming calls is another rare and uncommon scenario that is also classified as this issue. Under this circumstance, system errors and disharmony between call forwarding and settings can be regarded as the main cause of this problem. Meanwhile, it is accompanied by a spinning wheel shown in the Settings. It is commonly reported on the Apple Community and Reddit. System errors: All incoming calls are forwarded to voicemail. This could be remedied easily on Settings by following the methods in this article. Settings mistakes: The inappropriate settings on the Call Forwarding feature, network-related functions, and so on have the potential to interfere with the running of Call Forwarding. Of course, the causes are deeply hidden and not limited to these mentioned reasons in this article. Generally, different factors involving system glitches, carrier malfunction, and conflicting settings are responsible for an iPhone issue.

Why Is Call Forwarding Not Working on iPhone? Refresh Wi-Fi, Cellular Data and Bluetooth Quick Tips for iPhone Call Forwarding Issue

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