I'd experienced same issue. This troubleshooting steps help me, not once but 3times now. Im using evpad 5s since 2years+.
On the right of ur box, in between usb port, there's reset button.
Use pin to reset it
Before turn on ur device, press this button
Ur box will appeares red light.
Leave it for 1 min
Off n turn on back ur device. If still unable to repeat again.
This time after u press reset button, press ur stock remote power button.
It will turn off ur device, then use ur stock remote to turn it back on.
It shld able to load to main menu.

Just press the reset button to hard reset the firmware.
is as good as factory reset