Pixel 3 XL and Sprint - signal strength issues and sporadic calls dropping - any thoughts?

[MarcNJ]

I'm a Sprint customer (T-Mobile now?) and I just recently upgraded from a Pixel 2 XL to a Pixel 3 XL (running Android 10 - haven't yet upgraded to just released Android 11 yet). Since I've started using the Pixel 3 XL, I'm having all sorts of signal strength issues and dropped calls. While driving, my calls drop sporadically but frequently (in places that my Pixel 2 XL never dropped before). I was just in the supermarket (in Northern NJ) earlier, and discovered that my phone was constantly losing it's LTE connection when it was in my pocket (I would take it out to look at the supermarket app, and it would say I was offline until it regained an LTE connection). It's pretty frustrating since this is a brand new phone that I spent a good amount of time setting up. I am not sure if it's just a defective phone, or something else perhaps. Some thoughts about maybe what might be causing it:

- could it be the case I bought? I don't think so since I took it off in the car once and still seemed to have dropped calls

- On setting up the phone, I noticed two options that my Pixel 2 XL didn't have (WiFi Calling and VoLTE) and I've enabled them both. I thought I recall reading that VoLTE is possible now with T-Mobile's network. Could either of these options be causing the issue?

- Could my phone somehow be roaming on T-Mobile's network in general and they have weaker towers in my area, etc.?

 

Google has offered to replace it, but I have no idea if it's the phone, or the network, or something else, and would hate to get a replacement, spend all the time setting it up again, and then find out I'm still having the issues. I'm almost debating going back to my Pixel 2 XL since at least it worked! Definitely very frustrating! Any thoughts/suggestions/ideas/troubleshooting? Thanks!