add insult to injury
US /æd ˈɪnsʌlt tu ˈɪndʒəri/
UK /æd ˈɪnsʌlt tu ˈɪndʒəri/

1.
to make a bad situation worse by doing something else that is unpleasant or offensive
:
•
First, they lost the game, and then to add insult to injury, their star player got injured.
•
They cancelled my flight, and to add insult to injury, they lost my luggage.