Cassie has moved on with a new man, but it’s not sitting well with her ex Diddy.

Sources tells TMZ that the man Diddy hired to train Cassie was also seeing her on the side. Diddy’s trainer, Jamal Liggin, reportedly got so busy that he hired several trainers as backup, including Alex Fine, who Diddy called to train Cassie over the last year.

Diddy and Cassie announced their breakup last fall after a decade-long relationship, but sources claim Cassie and Alex hooked up before the split. Diddy reportedly feels betrayed by his ex and former employee.

However, sources close to Cassie and Alex refute the claim, saying that the two did not start dating until after she split with Diddy. Diddy is seemingly convinced there was an overlap.

Cassie hasn’t been shy to show off her 25-year-old boo on social media, posting PDA-filled photos. “Baby,” she captioned one shot. Diddy publicly proclaimed his love for Cassie on Instagram following their breakup.

Despite the drama, Puff has bigger things on his mind. The hip-hop mogul is focused on raising his children following the death of ex-girlfriend Kim Porter in November.