Restarting your iPhone is a common solution for a variety of problems. If no pop-up appears, then a carrier settings update probably isn’t available. If one is, a pop-up will appear within about fifteen seconds. Go to Settings -> General -> About to see if a new carrier settings update is available. Your wireless carrier and Apple regularly release carrier settings updates to improve your iPhone’s ability to connect to your carrier’s network. When other devices connect to your personal hotspot and browse the web, they use the cellular data on your cell phone plan. Sometimes turning cellular data off and back on can fix a minor software glitch preventing personal hotspot from working on your iPhone. Personal hotspot uses cellular data to turn your iPhone into a Wi-Fi hotspot.
