"SteveBell" wrote:

Bite the bullet and have a concrete grinder slope the concrete
properly. You'll be done and never have to worry about it again.

Alternatively, have a concrete company put a skim layer on top. These
aren't always successful, since they can delaminate.

There are also companies that will hydrojack the slab. Basically, that involves
drilling holes and injecting enough slurry to regain the slope that should be
there. Not particularly expensive, but it does require a crew that knows how to
do it as it is easy to break the slab if you do it wrong.