52% win rate most of the season and still can't climb out of B5 - B4

I have been having a constant win rate of 52% during this season and for some reason riot does not allow me to climb out of B5 - B4. When I'm in B5 i get 21 LP points for a win and when I'm in B4 i get about negative 20+ LP points for a loss and sub 20 LP for a win. A losing streak of 3-4 games will land me back in B5. Is LoL MMR screwed up or what am I doing wrong? Coz 52% means I win most of my games. So that means I should climb up but the MMR refuses to let me do that it seems. Any ideas about this behaviour of LP and MMR My profile is : https://euw.op.gg/summoner/userName=critical+realism PS:- I'm not implying I need to be silver or gold etc... what I'm asking is why does I get unfair deduction to my LP when I loose in B4 even with a 52% win rate. I think something is screwed up with my account.
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