2006 VW Jetta 2.5. The AC is not blowing cold air


#1

Hello, the AC has not been blowing cold air the last few days. when i turn the AC on, it works, the blower is working and there is air coming into the cabin, but it is not cold. I bought one of those DIY AC recharger and the pressure valve on it was reading in the RED. the instuctions for the freon can said that do not fill freon in if the meter is in the red zone. what is wrong with the AC and what do i do now? am i using the AC recharge pump wrongly, do i connect it and push the nozzle or just read the meter without pushing the nozzle on the can? any help would be appreciated.
thank you