Sagging rear end

So my old leafs were sagged out, about a 2 inch difference from tire to fender vs the front. shop offered to put on some 2016 leafs with 1200 miles on them for a reasonable price. finished up and 6 hours later they already look almost flat. empty bed no off road bumper or anything. im really confused and not sure where to go from here. it has a 2 1/2 inch block in the back. 6inch procomp lift with the black series coilovers on the front. any help would be appreciated.