Bricks, Masonry, Asphalt and Concrete - cement slab / brick water leak

I have a front porch that is about 4 ft high,18 ft long, & 6 ft wide. with laid brick. The front and 2 sides sit on a footer, the back is brick are what the rest of the house is faced with. The front corners, have a support posts that, supports the roof. The house was completed in 2003. The contractor is reluctant to look at this problem.

Problem: I believe that when they finished the brick work, they back filled the open area, with dirt/clay/sand, and probably took a tamper/compacter and then, poured maybe a 4 inch cement slab.
I notice that the back side of the slab seems to be slopping, towards the back of the floor, allowing the rain to run down between the slab and the brick.

What do you recommend that I seal this with, there is no large crack where the brick and cement have separated, the widest place might be 3/16 ".

Do you think that if I stop the water from entering, that, it will stop settling.
The front shows no signs of settlement.

thank you