why lte only option in the inner menu, falls back to 3g suddenly and the inner menu changes to lte/wcdma/gsm prl in redmi note 10 pro (opens in new tab)

Hi, I have gone to the inner phone information menu to change the pref network type to lte only so that i stay on 4g a;; tje to,e/ NIt siddem;u tjos cjamges tp 3g automatically without my manual changing it\. BUt once in 3g\. and stays there , until I again change it to Lte mode only \. The problem here i face is , sometimes in 4g \. ,u ca;; would not go through or the incoming call would get no response, but remain silent as if muted \. Is it phone settings, or glitch in network, How to\.\.\...