You don't need a new valve or spring (at least not yet, you don't). That valve will tap closed with a wood dowel and small hammer through the spark plug hole. Your engine is too new to have accumulated too much crud.
I will suggest either a small amount of spindle oil into the valve through the spark plug hole and let it sit overnight. If you don't have such oil, then buy some Marvel Mystery oil

and put a little in there instead.
Next morning, tap closed. Start car
repeat as necessary...as it may take a couple times to get oil down along the length of the valve.
The petrolium distilates are what will work along the valve stem to help free it up, and the TCP (Tricresyl Phosphate) will (hopefully) aid in it's continued freedom, as it is an anti-wear, high-pressure boundary lubricant. It is ideal for this condition, where valve-to-hole diameters may be a tad too close.
read lable on container and dope the fuel with recommended amount and drive the car.

Hopefully, this will fully resolve itself within a tankful, and then you're done with it. Do not add to the oil...ever...fuel only.
I rarely use this stuff, but can state from experience that this stuff freed up an exhaust valve that was absolutely insistent on sticking open on #4 cylinder on my runabout. Many repeated bouts of sticking with each drive. Finally used some MMO and it was fixed. It has it's uses.
I will happily sit back silently while I'm excoriorated for this advice by people who have not used it for this purpose, but KNOW it will not work. So be it; now have at it.