take off the paint, it should just peel off using your finger nails and fingers, ............. then, get some "extender" and I would also try to find some apple barrel gloss yellow.
try your paint, put about a table spoon in something, and put in a few drops of extender, ................thoroughly mix, and try painting again.
If that doesn't work, use the apple barrel gloss yellow and mix it with your yellow to get your desired shade/results, .................one of these two options should work for you.
