My nest dial won’t rotate to change functions or change temperature

[GT15]

My nest dial won’t rotate to change functions.  Worked fine then all of a sudden the dial no longer rotates. How do I fix or do I have a bad thermostat?

[Patrick_Caezza]

@GT15 

Pull the display off the base and ensure there are no wires or other obstructions that prevent it from rotating or sitting flush.

Carefully install the display on the base plate, making sure it seats properly.