Opponents leaving in fut champs but not receiving the win

I’ve just started my future champs run for the weekend. On two occasions I was winning in game but my opponents left before 45 minutes and I wasn’t awarded the win. 

The message prompts would just say the opponent has left the match and the match will be reviewed - not sure if this is an error or glitch but would love to get some help or clarity as I should have more wins than I already have.