Hi @Hakan Koese 

Welcome to our o2 Community.

Thats a really strange errror, which i have never heard of. 

Can you tell us what happens when someone is calling your mobile number? 

Does he or she gets some kind of error message like for example “the person you have called is temporarily not available please try again later”

Best Regards Matze 

Hi @o2_Matze ,

Thank you for your reply. I just asked my friend who tested my Wi-Fi call with. She said she heard something similar to what you said: ““the person you have called is temporarily not available please try again later”

Best Regards,

Hakan Köse

@Hakan Koese  Just for a quick test scenario: Could you please disable WiFi calling and ask your friend to call your cell phone number to see if she can reach out to you, and to be clear, you don’t have to answer the phone. It is just a test to narrow down the error. Best Regards Matze 

Hi @o2_Matze ,

I topped up a bit of credit and now switched to Ausland tariff. Now I can receive incoming call without Wi-Fi Call.

What do you want me to do next?

Best Regards,

Hakan

@Hakan Koese Okay, so to be clear: Incoming calls via mobile connection is possible and as soon as you activate WiFi Calling on your iPhone it is not possible to get through to you, correct? It is only possible to make outgoing WiFi phone calls, right? 

Best regards Matze  

Hi @o2_Matze ,

If it has nothing to do with my credit balance (before I load credits, it was almost 0), that’s exactly how you just described.

Best Regards,

Hakan

Hello @Hakan Koese,

you can try the following if you haven’t done already:

Restart the iPhone

Turn Wi-Fi Calling off and then back on

Connect to a different WiFi network and try again, as it does not work on all Wi-Fi networks.

Can you also let us know which IOS you have on your iPhone?

Best regards

Giulia

Hi @o2_Giulia ,

Thanks for the reply. My iOS version is 15.3.1.

Best Regards,

Hakan Köse

Hi @Hakan Koese, did you try Giulia's tips and did they help?

Kind regards, Ines.