Check the address that you are sending to.
Might be a typo.

Just because they are clueless about leds, and ruthless and mendacious about marketing, doesn't mean they want to risk legal action.
It's possible that their mailbox is choked with complaints.
It was a 3 day weekend.
Give them 3 business days to respond.

If you suspect that they have your address on a bounce list.
It's easy to create a throw away gmail address and see if it bounces too.

If so, they have an 888 number listed, call 'em.
Or hit the "chat" button and ask what's up with the emails.

Best to do these things before "plastering" without solid proof of their intent to defraud.

That will cover your ass, legally speaking.
Then go kick their's, angrily speaking.

Aloha,
Wee