Hi. I don't know how to fix this. I have mi 11 cn version flashed with eu rom.i have 5g and lte signal for both sim cards but they can't make or get in coming calls( my network tries to go back to 2g/3g signal to make a call). I tried both my sim cards to another phone and they are working just fine. I was able to manually switch them to both 2g and 3g with the other phone. I did the *#3646 thing to manually choose a network but it still doesn't work. Tried to reset this a couple of time and even reverted back to cn rom still no luck.