To create a list of devices that can connect to the hotspot, tap Allowed devices.
To set allowed devices:
Tap ADD (upper-right).
Enter the device name and MAC address then tap OK.
Tap the Allowed devices only switch to turn on or off .
If unavailable, from the Mobile Hotspot screen, tap the Network name (e.g. SM-T817V-xxxx, by default, xxxx is the last 4 digits of the Wi-Fi MAC address), then select an option:.