CHICAGO (CBS)–Popular punk festival “Riot Fest” is gifting fans with ticket specials after a hack left thousands of fans with limited or no access to three-day general admission passes when they went on sale in May.

Online ticket retailer Ticketfly was hacked on May 30, during the first day tickets went on sale for Riot Fest, a long-running Chicago music fest featuring artists like Beck, Elvis Costello and Blondie this year.

File image of concert goers at Riot Fest in Chicago. (CBS/Captured News)

Due to the glitch, many customers tried unsuccessfully to buy tickets.

Of deeper concern was the exposure of the personal information of thousands of Ticketfly users, which was accessed by the hackers.

Two months after the breach, Riot Fest is trying to make amends with fans. On Tuesday morning, all fans who had bought tickets–including those that bought them during Riot Fest’s holiday pre-sale and May 24 early-bird release–received a link via email to buy general admission passes to the festival’s 15th anniversary next year.

Those tickets will be sold at a special price of $99.98–the price of tickets back in 2003 when Riot Fest debuted. Current-day ticket prices are about $160 before fees.

The emails also included instructions on how to claim a complimentary ticket to this year’s show, which will be held Sept. 14-16 at Douglas Park.

Riot Fest founder Michael Petryshyn said in a statement Tuesday that there was only “one proper thing to do” to remedy the situation for fans.

“If it was only about the bottom line, Riot would have been sold to some apathetic conglomerate years ago,” Petryshyn said in the statement. “But it’s not about that–not one bit. Riot has been and will continue to be the festival that’s simply–different.”