Using USB and UART simultaneously

I have the Sixfab LTE/4G hat for RPI 4 and I need it for a project where I am streaming a video (internet connectivity has to be consistent) and at the same time need to get the RSSI value and do a USSD call through AT commands.
I tried doing this using the USB interface only, but I was losing network connectivity more than usual. So I enabled UART from the hat by soldering the jumpers and used it to communicate with the EC25 module through AT commands (using Pyserial). The streaming was still happening from the USB.
At first, everything seemed to work just fine, but after 5 mins, network issues will rise again.
So I would like to know if it is possible to use both USB and UART simultaneously or not?


Could you please share more details about your setup?
Which protocol are you using to establish the connection?

Which SIM are you using?
Which USB interface are using? for connection and for AT commands?
What is the signal strength at your location?
Which AT commands are you issuing to the module and how frequently?