Spent hours filling my cart with thoughtful gifts, making sure that I was ready to check out a good half hour before the end of the sale this time, in case checkout was glitchy again… 
Entered the 15% off coupon code, noticed that the discount was only $75 (oops! forgot that it’s not $100 until tomorrow!) — scrambled to whittle the cart down to $500 from $666.67 to take advantage of the full discount — checked the clock…15 minutes left… 
Raced to open up my email from Target with my eBay GC code and enter it…noticed that the 15% off code had disappeared, so I had to re-enter that…down to 5 minutes… 
Noticed that the GC hadn’t applied…re-entered the 13-digit number…this time, red error message: “This code can’t be used with the payment option you’ve selected.” Huh?!! 
Re-entered the GC…same red error message…2 minutes left… 
No time to figure out what was wrong with my method of payment — there certainly were no restricted items in my cart — nor to re-enter the 13-digit GC, so I blindly clicked the button to submit the purchase…spin, spin…$75 discount disappeared out of the payment summary…spin, spin…red error message appeared in the lower left corner of the cart announcing that the code had expired…spin, spin…no way to cancel the process at this point…
…spin, spin…congratulations, your purchase is complete, for the full price of $500 + tax…
🙀😱🙉
Refilled the shopping cart with cell phones for tomorrow’s sale, so as not to lose them to early shoppers; no longer under a time crunch, I did a trial run through checkout, but wasn’t able to re-enter the GC until I logged into PayPal. 
The GC was automatically checked and applied toward the new items in my shopping cart; however, not wanting to accidentally complete the purchase early, without a discount, I unchecked it, and it disappeared. 
How irritating!
The GC should stay visible at least until I log out of PayPal…
I plan on calling eBay customer service tomorrow to request a $75 credit (rather than be a jerk and cancel the entire purchase)…anyone have experience with doing something like that? 