Scott Disick was reportedly caught red-handed after leaving his cell phone unattended.

Scott Disick On Tying The Knot With Longtime Girlfriend Kourtney Kardashian, 'If It's Not Broke Don't Fix It'

For weeks, reports have been swirling, claiming the Keeping Up With The Kardashians star has been cheating on longtime girlfriend, Kourtney Kardashian, and now, a source claims he's doing so with the popular app, Tinder, and an "extra" phone.

“He says he only logged on out of curiosity and hasn’t met up with anyone," a source told OK! Magazine, according to a report on Thursday. "But Kourtney doesn’t believe him.”

Scott Disick Enjoys Booze-Filled Hotel Party While Kourtney Kardashian Cares For Their Three Children

Disick and Kardashian have been dating on and off for nearly a decade, and have three children together, Mason, Penelope and Reign. Unfortunately, however, his growing family reportedly hasn't been enough to stop Disick from partying.

"Kourtney used to be a partier when Scott first fell for her, but after kids, they have nothing common," a source told the mag. "He's told [Kourt] a million times she can't change him."

As TMZ reported earlier this month, Disick and a few friends recently let loose in Aspen, where they were reportedly seen drinking heavily, and possibly smoking pot. According to a source, Disick spent tons of money on hard liquor, and was charged a large amount after he allegedly trashed his hotel room.

Scott Disick will return for Keeping Up With The Kardashians season 10 later this year on E!