New Weak or no cellular network signal


Oct 13, 2020
I have here mi 10 ultra with the eu rom stable version. Since upgraded to this rom and my cellular network signal on sim 1 is always fluctuating from no signal to weak and to full signal. All this happens in the same spot. I mean if i sit on the couch i see the signal fluctuates. I have went back to 12.5 rom and this issue did not occur. I even tried another custom rom and did not face this issu either.
As soon as I switched back to eu rom i started to see this network signal fluctuation issue.

And this only happens on sim1 only. Sim2 is steady full all the time.

Is there anything i can collect to help you guys figure out what is happening?