Air Condition isn't as cold on 2004 Dodge Durango

My 04 dodge durango just came out of the shop for a tune up and replacing a crack cowl. Now AC is not cooling down as much as before. But at higher speeds if seems to be colder. Is it just in need of feron charging or a bad compressor? Could the past repairs affected the present problem? My durango has 109.000 miles on it.

Asked by for the 2004 Dodge Durango
which cowl was repl? if its in the dash this could be the issue. also could just need freon have it ck to verify freon level