Having the same issue with my 2021 F150, Ive called att and they've rest things on their end twice and it will switch to 4g temporarily, once I turn the truck off and back on it switches back to 2g and the truck hasn't moved at all, so the signal strength should be the same. Just wondering if Ford has a fix?Give ATT a call and they will reset the hotspot.
Mine is currently giving me only 2g and sometimes no internet at all. I think I’m going to have to take it to Ford. I’m in the Bay Area of California so I should have LTE coverage.