Hotspot problems

Use these steps first

Restart the iPhone or iPad that provides Personal Hotspot and the other device that needs to connect to Personal Hotspot. Make sure that you have the latest version of iOS. On the iPhone or iPad that provides Personal Hotspot, go to Settings > General > Reset, then tap Reset Network Settings.

If Personal Hotspot is not working on your iPhone or iPad (Wi-Fi

The Hotspot is a carrier-specific feature. Contact your carrier, if it is not appearing on your device.

Meanwhile...

Check the following

1. Network coverage and stability
2. Data Balance
3. On your windows (See if WiFi Auto Joins is enabled)
4. Also, check if you have any stronger WiFi signal around your computer.

Please avoid Hotspot and connect to the internet using wifi for any iOS updates

You may use a Hotspot of another Phone.

Watch the GIF for iOS update over Hotspot on iPhone

Watch the GIF for iOS update over Hotspot on a PC/Mac

You are addressing this to another user and not to Apple in this forum.

Apple Support Community Forum

This is Apple Support Community forum, primarily for a user to user interaction for information & idea sharing between users, if need be, extend support on technical know-how in handling Apple products from a more experienced fellow user, This is not the right forum to discuss with Apple Inc.

The Hotspot is a Carrier Specific feature. Contact your Carrier (Cellular Service Provider), the agency that issued the SIM / eSIM to you.