How did my damage decreased instead of increasing throughout the game

[egmnzztrk]

Match ID: 48441984

While I was playing Vyper today, something strange happened.

My ''damage to players'' shown 11.5K damage, that felt too low and then I checked the graphs. Somehow my damage started decreasing at some point, the graph shows, I never see that before.

But if I check another graph (Pic. 2) I can see my total damage to players with multiplying my damage to heroes one by one.
My damage supposed to be around 43K

Is this a bug or something I don't know about...

 

[styllarr]

It's a known bug that's been around for a while.