Why won't it work after switched on

I have just bought a board scooter smart balancing

It worked fine when my daughter turned it off on remote control then went to turn it on it stays in self locking mode

Have tried to unlock it with remote control and by switch but no joy left it switched on all night innthe hope that it would rest it self but alas no it didn't

It's my daughter's birthday today and she upset that she can't ride it now Ian at a loss can anyone help