2009 Mitsubishi Galant AC problem it's not the compresser it actually works fine

What is your question?

The compresser is definitely working right it is kicking on and off the way it should on my 2009 Mitsubishi Galant but green AC light on the AC knob inside the car is blinking on and off and the air blowing out of all the vents is really warm. After replacing the lower schrader valve and charging the air with a A/C Pro Ultra Synthetic A/C Recharge R-134a Kit it worked great but only for a day or so and then the green AC light on the knob starts blinking on and off and the air blowing out of all the vents turns warm again. I charged the air again and it worked great for about the same time of a day maybe 2 before the green AC light starts blinking on and off and air blowing out all the vents turns hot again!! Thank you for your time reading and any suggestions would be greatly appreciated!!

What makes this problem better or worse?

Charging the air but only blows out cold air for a couple of days.

How long has your 2009 Mitsubishi Galant had this problem?

1 year.