Your match history in Rocket League does not represent your actual matches (due to technical limitations). Instead, it represents changes in your stats between your profile updates. The date that you see in match rows is the date when we detected some changes in your stats between updates.
For example, if you played a match yesterday and visited your profile on our website today, you would see that you played the match today, not yesterday. To avoid it, you should refresh your profile regularly (ideally, between each match). In this case, the dates will be close to the real ones.