I have written about this in the past. I win match and lose SR.
I was in the middle of my rank bar. I just won two matches as tank in a row, but my current match I’ve lost all my gains for my current rank bar and it shows -% of how much I lost with a Demotion protection notice.
How does it make any sense that I keep losing rank after a Victory? Why does this keep happening?
And no it’s not a visual bug as some have suggested in the past.
You shouldn’t lose progress after a victory.