Iphone XR Carrier data internet slow

Bought a new Iphone XR the other day from Metro PCS. From the get go I have been experiencing slow data speeds. I am in the LTE both in map and on my phone, my phone only shows a few bars, but im directly in the green. Yet I get less than 500k download and near 4MB upload. Already spoke with Metro PCS and it has nothing to do with their service. Tried speed test in different location miles apart and still get the same results. What is going on with this new phone and how do I fix it?

I have already tried the airplane mode, then back on, resetting networks, restoring phone, and so far nothing has worked. I am NOT RESTORING FOR A SECOND TIME!!!

also all my messages until I delete the entire thread says "from primary number" when someone texts me. This dual SIM is BS who the *bleep* has two carriers on the same phone,, what the *bleep* reason....

Works fantastic on WIFI