No chemistry between the lead actors at all
Not for a second did it look like those two people were connecting at all. Every scene between them was awkward. They rushed their delivery of lines, didn't seem to be listening to each other or reacting to each other. It just didn't work. They were bland and uninteresting.
Kevin Hart had a few good lines. Regina Hall was a bit annoying sometimes but also funny many times. Their relationship was the only interesting one in the film.