Refer not cooling right

I have utily refer hd3 old unit 2005 , by thermo king,it took allmost 6 and half hours,to cool down to -5 set at -10 ,is that normal for a old trl,so im at the love in ms ,and thinking low on freon ,waddel over to shop ,says they dont do work on refers ,but told me freon is green,um dont think so ,freon a clear gas ,so i walk away ,cause he didnt know crap about them ,the temp outside at 9 pm was 90 degrees ,humitdy was 95 %,now at 3:45 its 79 degrees and 78 % humidty and keeps cyling from high to low side the engine does ,it does not work very good ,when sun beats on ether ,works hard to maitain temp

 

I defrost it when i parked was in thermo king thurs replace the upper rad hose and they power wash whole engine so im unshure they cleaned that or not

 

Ok thanks i know it was a long shot to ask her too but thanks in advance to everyone for there help

 

Ok thanks

 

no im empty now, thought i try a test on it, didnt see no bubbles in the sight glass on the dryer, went from 9pm last night to 7 am this morning , and still only minus 5 and set at minus 10 so i guess thats normal for a empty trl with no product as i figure the product will take it down to the rest of the way thanks everyone