If you have a multimeter check the resistance at the connector that plugs into the board. Also check what it says the temp is with the thermistor disconnected and shorted to give you a clue what's happening.

I got this one when I broke mine, it screws in so no crushing it: https://www.amazon.com/gp/aw/d/B07B3W8XQ4/

I pulled the wires out cleaning off a huge blob of pla from my hotend. I can't remember what my symptoms were but I feel like I saw something like you. My best guess is that it's shorted, disconnected or you crushed the actual sensor.