Try updating the network driver of your PC/ Laptop. Control panel> Hardware and sound> Device manager > Network adapters - here you will get the name of the specific network adapter in your computer. Search for network adapter drivers for your Windows version and manufacturer (hp , Lenovo etc.). Download and install the latest driver available.
I just went through an hour on the phone with Lenovo bc I was having the same hotspot problem. After getting no help from their India helpdesk (it was truly hard to understand from accent and terrible connx), I went to Best Buy and tried my luck. I was able to login on the HP spectre series, but nothing else. The solution was to switch my SG21 to 5gHz. Tap on the hotspot in your phone to pull up the password in order to change that.
