If implementing the Pi-Star Remote commands on your radio for use with your hotspot, KE0FHS has a good explanation here --
https://amateurradionotes.com/pi-star-n ... #watchdogs -- on how to set up the reboot and other commands.
However, for my TYT MD-UV380 and probably other radios, there is one more step to be done.
The reboot command fails unless you uncheck the "Private Call Confirmed" checkbox on the codeplug's "reboot" Channel Information sheet.
Otherwise, on the hotspot, the DMR logo just shows up on the OLED screen over the rolling MMDVM logo. A ~2 second PTT keypress may be required; the hotspot may not immediately reboot.
HTH.