2004 Jeep Cherokee Air conditioning Dosn't Cool enough

I have this problem with my GC. The air condition in the cool position feels like the air is not cool enough to keep the temperature inside I check the refrigerant and changed but didt'n work so I took a air condition tech and checked. he told me that don't have any leak an the compressor works fine so he thinking the have a ploblem inside or somethig bloking the line. So i took home and removed dasboar because I red that some times the litle doors inside get broken but find the they worked properly, I don't no what I should do now.