Hotspot Not Working

Here's the issue I'm having: When I activate the hotspot feature on the iPhone, the Wi-Fi access point doesn't start. I can access the hostspot through USB or Bluetooth, but not Wi-Fi. If I change the hotspot password, it will appear for a minute or two, then stop working again.

I have already reset network settings, and done a full wipe of the phone with no improvement. I can use Wi-Fi normally, only the hotspot seems broken.

Any ideas?