Phone call issues

[Hskloo1]

I am using the S21 Ultra and am having issues with regular network phone calls.

Most of the time, the line is completely silent for both the caller and for me.

I have ruled out the SIM, any network faults and it seems to be related to the software. 

WiFi calling works fine however this isn't an option in most places.

Is anyone else having issues with this? I have disabled 5g and also 4g calling. 

[Ventor]

Hi, have you tried resetting the APNs?

[Ventor]

@Hskloo1 Other things you could try are:
In phone app storage-delete cache and data.
In terminal settings-Reset network settings.
Put the phone in Safe Mode and try again if the problem persists.

[Hskloo1]

I have reset all apns, cleared cache and switched phone apps and also tried safe mode.

The issue persists

[Ventor]

@Hskloo1 Es mucho trabajo, pero Factory Reset es el último recurso para intentar solucionar este problema. Prepara una copia de seguridad, extrae la micro SD / si la tienes / y procede. No restaure la copia de seguridad.
Si lo desea, espere otros consejos de la comunidad.

[Hskloo1]

I have factory reset the phone, the issue persists.

[AndrewL]

@Hskloo1: Can you try heading to the Samsung Members app > Long press on the app icon > Diagnostics, and run through the Microphone and Speaker tests respectively. If you encounter any issues here, then please reach out to our Help Desk via the link below, and an advisor will be able to assist you further.

https://www.samsung.com/uk/support/contact/

[Abbas Allawy]

I'm facing the same issue

I have to restart the mobile just to make the call. And after while it goes silent again.

Can you please advise if you solved the issue?

BTW, my mobile is s21 ultra

[Hskloo1]

Hi, i have solved it using a workaround. It seems to be caused by a 4g calling issue.
If you go to settings and under mobile networks change the network mode to 3g only and also disable both 4g/lte calling and WiFi calling, the issue should be gone fully.
Its not ideal as you can't use 4/5g but it has solved the problem for me.