Help needed please guys

Placed this multi on this afternoon match, which BF originally said was a winner, but then subsequently declared my Over 40 booking points to be a losing leg and took back my winnings. There were 5 yellows shown, so at 10 each that makes 50 to me...or am I missing something?
Thanks.
Same Game Multi (x3)
Sheff Utd v Bournemouth
W
Corners Over/Under 11.5
Over 11.5 Corners
W
Match Odds
Sheff Utd
L
Card Index
Over 40 Points
Combined odds:
11.01
Stake:
£10.00
Returns:
£0.00
Bet ID: O/0008230/0000265