The former Apprentice candidate, 27, was accused of cheating on the Love Island presenter last week after a woman claimed Brady “took [her] back to his”.
Proving his relationship with Flack is still going strong he posted a picture of himself with his arm around the TV star as he planted a kiss on her nose.
He captioned the shot with a heart emoji and the word “perfect”.
It comes days after Brady was accused of cheating on Flack during a night out in Chester.
According to photographs published by The Sun, the accuser commented on one of Flack’s Instagram posts. The since deleted post allegedly read: “Ahh interesting. Got with him in Rosie’s nightclub Chester when he did an appearance on Gay night, took me back to his.
“Then completely ignored me after. Lovely guy @CarolineFlack.”
Brady denied the claims insisting he had “never seen [her] in my life”.
Flack, 38, addressed the accusations as she flew solo at the TRIC Awards on Tuesday.
Speaking to reporters on the red carpet she told Mail Online: “My relationships are the same as everyone else’s.”
The TV couple confirmed their relationship earlier this month by posting a sweet snap of them kissing in the snow.
The pair were rumoured to be dating last month after meeting at a showbiz party following The Apprentice star’s stint in the Big Brother house.