First Update iPhone to newest iOS update

Delete All previous Saved Networks - (settings, More Settings, Network & Internet, WiFi, Saved Networks,
Press and hold each saved network - should give option to forget device)

Set your iPhone Hotspot Password to 9 Characters or Less (all lower case)

Example - Password - cheesedog

Also set Mobile Hotspot Name to something Simple like 1 Word - 

Example - Hotspot Name - PhoenixAndroid