Checking the voltage at the receptacle and a surge protector as already posted is what I would do.
With that checked off it's the machine, the electrical systems are real cheap, no relays, no nothing, meaning that if button/light/wire goes bad it messes up the whole thing.
The hard part is finding the bad part, there's no way to know where to start.
You have to make it clear that you're not going away until it is fixed, whatever that entails.
Some company's are better than others.
BTW I don't own TL so take this post for whatever you think it's worth.
Good Luck.