LP GAINS BUGGED ?

Heya, So I have been on Diamond tier for a while D4-D1 , currently D3, on TFT and I have noticed that LP gains are getting way too ridiculous.For example, I did 3 games this morning 2 wins and a 7th place. I gained 24 , 25 and then lost 50.How is this remotely fair ? For the past weeks it has been very hard to do any climbing due to this...The above example is not even the worst I have experienced but it just really put me off from playing. I understand how MMR impacts your LP gains (since I have been playing league for a couple of years and have understood it). I'm not above my elo , If anything now I'm lower since it´s almost impossible for me to gain LP unless i finish top 3, since even top 4 most times doesn't give me any points. I believe that the system at this point is glitched or just faulty on it's roots when you play a certain amount of games.Wouldn't it be simpler to give a set amount of points always regardless of MMR for 1-8 places? 1st place gets 50, 2nd 30, 3rd 10, 4th 5, 5th -5, 6th -10, 7th - 30, 8th - 50. This would really tackle a lot of the issues that surround this problem. If I have a bad game or try to do something that is not meta I have lost 60-70 plus points on a 8th place game!! That means I need to win 4 games more or less just to compensate that. It makes 0 sense and it discourages anyone to grind or make a serious attempt to climb. Match history If you look at my match history out of my last 17 games I won 7 and finished last 3 times and got a 7th place once. So from the 17 games 4 times I should have lost LP and 13 times I should have won. Any thoughts if there are any issue going on or a reason why this seems so unbalanced? Thank you ,