paint flaking off after three months!

[SuperDutyScaler]

i washed the cab originally, then scuffed it with i thought 1200 wet/dry, then i painted with the paint i posed above. But last night i washed the paint in 91% rubbing alchol and it came off without any fuss. So now the big question do i now wet saned tas much as possible with the 1200 w/d or do i go deeper like 600 first then 800 and then finish with 1200 and then clean the body and finish with the grey scotch brite and then just hit it with my new Dupicolor paint?