My wife and I each have a Fairphone 4. My wife is now experiencing the problem that she cannot make or receive calls (error message: mobile network is not available, German: Mobilfunknetz ist nicht verfügbar). Her SIM works perfectly in my smartphone, but my SIM does not work in hers. The problem is persistent. So it’s clearly a hardware problem. Does anyone know of this problem and possibly a solution?
Is your phone also a Fairphone?
If not, then the SIM of your wife could be to old.
… they both have a FP4, as he said 
2 Likes
Of course your phone should be able to use a physical SIM.
So I would suggest you contact support. It will a long time before support get in contact with you.
Is an e-SIM an option in the meantime?
Thanks for your response, but I fear an e-SIM would face the same problem, which seems to be a hardware fault. Do you know where in the phone the function “phoning” is located and whether this module can be exchanged?
I really think that an e-SIM can work if a physical SIM doesn’t.
As an e-SIM is all software, no hardware involved.
As far as I know the physical SIM is on the motherboard.
Well, have you taken into account that mobile data actually does work in my wife’s phone?
I fear I forgot mentioning this important fact in my question, sorry!
Mobile data depends on a working SIM.
Interesting, so it seems to be related to the radio access technology which the phone is using. What about the VoLTE settings? It seems like for calling the phone needs to switch away from the working data connection (4G/5G) as it cannot handle the call there. It tries to fall back to 3G first but depending on the provider there’s not much 3G left in Germany, so it falls back to 2G and here it goes wrong - something like that. So check if the phone is configured to use VoLTE (may also be called “4G Calls” or “4G-Anrufe” - you’ll find it via the search in the settings) and see if that makes a difference.
1 Like
If the phone doesn’t see the SIM, one can’t alter the settings.
But that was never said, he told us that the network is not available, not the SIM.
Exactly. The SIM is not the problem, obviously.
Thanks a lot, Martin. The VoLTE setting solved the problem!! Great!!
1 Like