Oh it's Polish people more than fandom btw (even though fandom is also not loving the particular song either).
Polish people thinks TVP rigged the entire NF in favor of her and the people are literally mad about it. They want EBU to disqualify Poland from the contest. They started to mass streaming RAFAŁ's "The Ride" (who is considered as another "TVP puppet") to push Blanka's song back in top lists.
Polish people wanted Jann to represent them in Eurovision, and according to some allegations Jann received 3 times more votes than the 2nd place Blanka and juries tanked him. TVP never revealed the detailed votes and everyone is left with the point scoreboard (which eliminates any voting weight).
More brief details is here
, but if she wants to qualify she really needs to hit that notes.
Edit: I'm not saying how she's getting treated is rightful, I just wanted to give light to the situation.