I am on the visible unlimited plan. I recently got a new phone and am trying to connect to my Hotspot for the first time. When I go to turn it on a pop up appears that says "checking subscription status" and then disappears. After multiple times of this, my hotspot finally turns on, however I then can't find it in my networks list on my laptop.
You didn't mention what phone your are using. Far an android phone go to setting, then click on network & internet settings, then hotspot & tethering, tap wi-fi hotspot, make sure hide my device in not checked. That would be the only thing I can think of that would block you from not seeing it on another device.
If you have an iPhone, maybe another user can help.
I have the same problem with my Moto Stylus 5G 2021. Hotspot worked perfect with a Moto G7 but got the new phone and won't work. I contacted support chat on 1/10/23 and they couldn't fix it. I am still waiting for a fix from upper tier support.
I did notice when I try turning on Wi-Fi Hotspot and get the error pop-up box, if I just tap the home button the hotspot stays on. My TV or laptop connects to the wi-fi but there is no Internet connection. If I click the ok button in the error pop-up, the wi-fi hotspot turns itself off. Hopefully it gets resolved soon.