It seems like when I play Puzzle Rush some low-level puzzles are excruciating while higher level puzzles can be simple mates in one.
They have added new puzzles recently. It is possible some of the new ones are misrated.
Looking at your last 25 puzzles, you failed to solve these two:


They were rated around 1300. I think that rating is pretty accurate.
It seems like when I play Puzzle Rush some low-level puzzles are excruciating while higher level puzzles can be simple mates in one.