Why does my phone fail when it needs to go from 4g to 3g in incoming calls?

[Windows Central Question]

my phone fails when it needs to go from 4g to 3g in incoming calls

Sometimes incoming calls fails because it needs to go on 3g to recieve the call.it keeps stand on 4g

 

[TechFreak1]

Re: my phone fails when it needs to go from 4g to 3g in incoming calls

That is most likely because your in area with bad signal, the only way to check if it's your phone is to put your sim in another phone and check if the same happens or go to an area which you know has full signal and check - if the same happens here on both phones, you may need a sim replacement.

Also you will need to monitor this behaviour over a period of time.

Lastly 4g is currently only for data not voice, simply put voice only goes over 3g and 2g until Voice over LTE (VoLTE) is rolled + activated in your area.