The first thing I'd check is the refrigerant. You can take it to an AC place, get some gauges and a can of R134a, or use a product like AC Pro, which is available at Walmart. I have used AC Pro to recharge my 04 every spring for the last four years or so.

https://youtu.be/0RkJDfmJXBE

https://www.walmart.com/ip/A-C-Pro-A...0-oz/353326131