iPhone SE (2020)

[DPRK]

Weak signal & data slow and sometimes not working even though I reside in a big City with several cellular towers nearby. Anything I can do?  What are the correct APN settings?

[Mark613]

Upgraded to newer firmware to see if it helps. Also try this in different location to see if the weak signal is location problem

[Grinch]

Have you had any work done on the phone that required it to be taken apart. It is possible that the internal antennae was not re installed properly. 

Try a full reset of phone. 

[softech]

@DPRK 

APN settings only helps when you not getting data at all.  If weak signal, slow data , it won't help

check your phone and see which network you are connected to.  Whichever plan you have, you can access 3G , 4G and 5G network.  So, go to your network mode, try each one and see which one give you the best speed