Temperature gauge is not moving to middle mark on gauge . ?

Definitely thermostat. It's actually an easy fix if you're a handy person - saving you $$$ from dealership labor costs. Lot's of YouTube videos to show you how. The part alone isn't expensive.

Could be there is an air pocket right where the temperature sensor is.  The sensor measures the temp of the coolant (not air). Find out HOW TO REFILL THE COOLANT Proper step by step.  Maybe the previous owner filled it the Domestic car way(done on older vehicles where the thermostat is at the top of the motor) (new style engine have the thermostat down deeper in the engine so the refill method is different)  You can either get a repair & maintenance manual from the public library or Google it.  We do that when we do not know.

Thermostat could be stuck open.  Replace it.  No luck, get a scanner and check temperature readings.  Temperature is normal in scanner, gauge is bad.  Temperature is showing cold, ECT sensor could be bad.  Good luck.

Have you checked the coolant level? You may have an air pocket in the cooling system and if that's the case you might be over heating the motor without knowing it. Temperature gauges are not accurate when air is in the cooling system. Take it to a mechanic right away.

Thermostat is jammed in the open position. Fit a new one asap as at the moment your car is using more gas and increasing wear.

Bad thermostat..........