Who I have the same questioned this topic

At home, my phone went to 4g and mobile internet was fine. I'm at work now and it went to 5g and now mobile internet is NOT working. I have done everything they said including a factory reset and STILL NOT WORKING. I toggled airplane mode again and it flipped for a moment to 4g and mobile internet worked. Now it's on 5g and isn't working again and this phone will not let me move to 4g manually. FRUSTRATING!