• To begin, make sure Bluetooth is enabled on your iPhone or iPad. To do so, go to your device's Settings app. Make sure the Bluetooth button is green at the top of the list, and if it isn't, swipe it to the right. Allow New Connections if prompted. This will allow your device to connect to new devices.
• After that, make sure AirDrop is enabled. Select General in the Settings app, then AirDrop.
• You can then choose whether AirDrop should be available to everyone within range or only your contacts. For the sake of expediency, select Everyone to see if it addresses the problem immediately. It also doesn't hurt to try turning AirDrop off and on again to reconnect - choose Receiving Off to turn it off.

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