Huawei
Call Forwarding Between SIM Cards auf Huawei
On dual-SIM Huawei phones, each SIM slot handles calls on its own network. If SIM 1 loses signal, is switched off, or has no active plan, calls to that number are not automatically routed to SIM 2 unless you turn on forwarding between the two SIMs.
This setting sits inside the SIM management section of Mobile network settings, separate from regular call forwarding to another phone number. It only redirects calls between the two SIM slots inside the same device, not to an external number.
To turn it on or off: Open the settings ➤ Tap on Mobile network ➤ Tap on SIM management ➤ Tap on Call forwarding between SIMs ➤ Activate the option you want.
Once active, an incoming call to the unavailable SIM gets rerouted to the SIM currently online, so you still receive it. Turn the option off again if you use both numbers separately and want calls to stay tied to their own SIM.
If you actually want calls forwarded to a completely different phone number instead of your second SIM, use the standard call forwarding option under your carrier settings instead, since this feature only works between the two SIM slots in the same device.