If you can't use your mobile phone as a personal Hotspot, there may be several causes of the problem.
To use your mobile phone as a personal Hotspot, you need to turn on the function and establish a connection from the other device to your mobile phone's Hotspot.
Solution: Use mobile phone as personal Hotspot
To use your mobile phone as a personal Hotspot, you need to key in the password you selected when you set up your mobile phone as a personal Hotspot on the other device.
Solution: Check the password for the Hotspot on your mobile phone and key in the correct password on the other device.