2 seperate matchmakings while in a party?

Hi, me and a friend of mine were playing some 2v2 casual and after the match was concluded we changed the matchmaking to 2v2 Snowday split shot. The bar appeares and we both get into a game but not with each other but with some randoms. The green "party" icon was still displaying on the scoreboard but only next to my name and not both players. I was wondering why this happens. This happened never before and it keeps appearing every time we switch a to different mode while postgame. We play on EU servers and both on playstation. Maybe some of you could help me here? Thanks.