Lynn Hung recently confirmed her engagement to businessman Ken Kwok and are expected to marry in December this year.
However, Ken's ex-wife Ami posted an old birthday celebration photo with Ken.
His hand is around her and they look close and happy so it is speculated that she did this to spite Lynn.
According to Asianpopnews.com, when asked about his ex-wife posting the old photo, Ken replied: "I did not notice as I do not use Facebook.
However, an hour later Ken contacted a reporter to say that it was just an old photo that Ami had not deleted.
"We are still friends, and we broke up amicably. There is no unhappiness. Our personalities are not compatible. We filed for divorce on April 2014."
He also revealed that he does not have much contact with his ex-wife and are just "normal friends".
He stressed that Lynn was not the third party:
"I knew Lynn after I was divorced. You can say that we progress too fast, but such things can't be explained."