Mine does that too I'm at level 2820. I press the power button in the game to make it restart and it fixes it for me! Try to press the little power button in the game and wait for it to restart it should put u at ur regular level!
I'm on my Samsung Galaxy J7 Refine I'm at level 1815. It happened the last time they had this event too. I feel like I'm so far behind the other ppl in my "group" because of it!