Thank you for your response.
I made sure I am selecting the right inlet again in fluent and it is displaying the correct dimensions as in image 1. The distance between the walls is 10um and I am using a reference depth of 1500 um so the area should be 1.5e-8 m^2. In cfd-post the same area is displayed as 1e-12 m^2 in image 2. I thought maybe cfd-post didn't pick the reference depth from fluent but if that is the case then the area should have been 1e-5 m^2 with the default 1m depth. I am not sure why, but it seems like there is a thin depth in the y-z plane that cfd-post added which is causing the wrong area (see image 3) but I am sure my geometry is only a rectangle and the analysis type is 2D. Any idea on what is happening?