T-Mobile’s latest “un-carrier” move — an attempt to reward its customers with freebies offered via an app called T-Mobile Tuesdays — has been just a bit too popular. Demand for the app and its various promotions was so high that the app crashed under the influx of customers right out of the gate. And now, one of the best deals it offered — free Domino’s pizza — has been pulled. According to T-Mobile CEO John Legere, Domino’s couldn’t handle the increase in order volume, and has pulled out of the promotion indefinitely.

Knowing that the loss of the Domino’s deal would be a blow, the CEO placed blame on the pizza chain and even published an internal Domino’s memo explaining why the company was exiting the promotion.

Among other things, the memo told its retail staff that it knew the program had “put a lot of stress on your stores.”

“After reviewing yesterday’s results and taking your feedback into account, the decision has been made not to continue the T-Mobile Tuesdays promotion unless we can find a solution that is best for the brand,” the memo read.

Legere’s tweet also noted that Domino’s stores saw three to four times the volume of a typical Tuesday’s sales.

3/ OMG @TMobile customers slammed @dominos stores!! They saw 3x & 4x in a typical day and can’t handle the volume. pic.twitter.com/jVvDGAqduS — John Legere (@JohnLegere) June 15, 2016

But while the increase in pizza orders was clearly a factor in T-Mobile’s decision, the promotion was already leaving T-Mobile customers upset when they found out that Domino’s was limiting the number of free pizzas per store due to promotion limits. Stores stopped accepting the coupons for the free pizza provided by the T-Mobile Tuesdays app, which left users frustrated.

Plus, in what was a huge oversight in crafting this deal’s terms, T-Mobile customers on a single family plan could all use their own codes to place large orders of multiple pizzas. That is, T-Mobile was actually offering the pizza giveaway to anyone with an available line, instead of just one free pizza per account.

It’s unclear why Domino’s wouldn’t have limited the deal as one per household at the very least. A number of customers reported they were able to stack the coupons from family members to get more than a single pie.

In a statement, Domino’s acknowledges that the way it handled the promotion disappointed customers, which is why it’s exiting the deal.

“The T-Mobile promotion generated an overwhelming response… we are happy so many of their customers love Domino’s,” a spokesperson told TechCrunch.

“The demand was significantly above what we agreed to in advance, which resulted in an understandably disappointing customer experience for some. As a result, we are re-examining the future of this promotion. We thank everyone who participated in the promotion and thank those individuals working in the stores who went above and beyond in trying to keep up with the overwhelming demand,” they added.

While some people argue that not getting something for free is not actually a loss, and therefore customers shouldn’t complain, that’s a narrow view. This sort of promotional misstep can impact how people feel about a brand. If you say “thanks, here’s a coupon,” and then that coupon doesn’t work, customers feel slighted. When the goal is to promote the brand and make customers feel appreciated, that’s a sizable failure on both T-Mobile and Domino’s part.

Despite the setbacks, the T-Mobile Tuesdays app is still topping the charts. It’s currently No. 11 on the iTunes App Store, after hitting the No. 1 position on — you guessed it — Tuesday. Even at its lowest point, it was still ranking No. 51, which is a more than decent spot for an app of this nature. According to Legere, the app has already been download more than 2 million times.

T-Mobile has since replaced the Domino’s promotion with Lyft, which is offering free rides (a $15 value). The app also includes a free Vudu rental, free Wendy’s Frosty and a $20 coupon at MLB.com, among other things.