I can hear them talking, but they cannot hear me!

[gbhxu]

It does not matter if I'm calling them or they call me. I often get the situation that they cannot hear me.

Any ideas?

[bristolian]

Is this specific to one location, or does this occur everywhere? Does speech drop out permanently or is it varying?

Does VoLTE (Android) or 4G-calling (Apple) show onscreen when this happens? It should be next to the signal indicators.