My situation is slightly different from most of you but i found this post because I was having the exact same problem. Hotspot disconnects at random. Maybe on for 5 mins, maybe 15 mins next time. Maybe 2 mins after that. Who knows? I sure don’t.
Im running iPhone XS Max, iPad wifi+cellular, and MacBook Pro running Windows 10 on bootcamp. I do vehicle diagnostics and reprogramming for a living. When i flash update a cars computer, i need a steady internet connection for anywhere from 15 minutes to an hour. If the update is interrupted for any reason, i will be buying my customer a new computer out of my own pocket AND trying the process again. Being an Apple loyalist, you can imagine my frustration. I have been very blessed so far and have not had the disconnection during a programming event. Here’s how I managed to work around this problem.
I noticed years ago the hotspot issue with iPhone. I also noticed that when i use my iPad as the provider of hotspot, i got much longer connection times, but still not indefinite. After finding this post, it gave me some ideas and i found something that worked for me. I always restart my iPad first. I go into settings and set auto screen lock to “Never”. Then i go to the hotspot page and turn hotspot on and I LEAVE THAT HOTSPOT PAGE OPEN WITH SCREEN LIT UP AND IPAD PLUGGED IN TO CHARGE AND I DO NOT TOUCH IT FOR ANY REASON!!! When i do this, my MacBook stays connected on hotspot for a very long time. I have never had the connection drop at all since I’ve used this method and i have tested 12 hours of continuous connection time. I know someone’s gonna say “it won’t disconnect if you connected to a MacBook” but i promise you that’s more a MacOS thing because im running windows on my MacBook Pro and without this method, depending on apple’s hotspot is like playing russian roulette with 5 bullets.
As i said in the beginning, i know my situation is slightly different as im working with an iPad with cellular. I have not tested this method using the iPhone as the provider of hotspot because it’s nearly impossible for me to set my phone down and not touch it for any amount of time. I imagine it “should” work the same. Maybe I will test it sometime soon.
It’s not a fix, but it worked perfectly for me. And it’s better than buying an android (YUCK!)