OREANDA-NEWS. June 08, 2016. Today was supposed to mark the start of the carrier's big thank you program, which includes free stock and pizza. All customers had to do was open up the T-Mobile Tuesdays app to redeem their prizes.

Unfortunately, the app hit a snag in its debut.

The popularity of the T-Mobile Tuesdays app -- it's the fifth-most popular free app on Apple's App Store -- overwhelmed the company, with customers complaining about server errors or being unable to even open the program. It's a bit of an embarrassing wrinkle for the usually slick company, which has used various "Un-carrier" programs to drum up attention for its service.

"Still down," a Twitter user with the screen name @AndrewPunch tweeted in the afternoon. "Never underestimate the demand for free pizza."