2005 Dodge Neon

It sounds like you could have a coolant leak and there is an outside change you have a blown head gasket as well but to be sure lets run down these guides to help us pinpoint and fix the issue.

https://www.2carpros.com/articles/engine-overheating-or-running-hot

and

https://youtu.be/5zpNjYmmiYY

and

https://www.2carpros.com/articles/car-is-leaking-coolant

and

https://www.2carpros.com/articles/replace-thermostat

Let us know what happens and please upload pictures or videos of the problem.