Bad experience with Flexispot checkout.

I wanted to buy the Flexispot E7 Pro, and I had everything ready after selecting the specs. The site offered me $30 off for giving my email and another 30 off for some other site deal. I proceeded to checkout and after I gave it my credit card info it froze and emptied my cart. Now, going back and doing it again, the coupons wont work.

This is pretty frustrating.