Gained 9 lp when previously gained 20lp

So I won a game and was at 62 lp and gained 20 lp putting me at 82lp so I figured another win would get me to my series. I proceed to win my next game as seen in discord app link however I only gained 9lp and I am severely confused. My entire team also received between 9 and 10 lp and everyone was very confused as seen in the end game chat room. Even if i was a lost prevent I had received no notice from riot saying so and have no clue as to why this would occur as I have had games that were more of a stomp without this loss prevention. I would hope to receive some kind of a notice if a loss prevention would come because right now that is the only reason I can think of that I would gain only 9 lp when I should currently be in my series it is ntot that it has been a major impact it is just very frustrating because with that win I should be in my series. Also here is my op.gg to prove that my mmr is not total garbage even if I have had some bad games I am nowhere near the elo hell of gaining 9lp and I have never had this occur before. https://na.op.gg/summoner/userName=AWESOMEROTON647. Hopefully someone can help shed a light on this issue. Thanks, A fellow summoner