Water pooling in backyard only after my deck was constructed

I have a 3 story TH w basement walkout. I recently had someone construct a deck but now the yard area under the deck pools with water after each rain. It was not like this before. Is it possible the contractor cut through some part of necessary drainage system while digging the holes for the posts? Will this begin to drain better with time? If not, what do I do??

The home is build into a hill (The front door is located at the main level/1st floor) and already has a sump pump, but should I be concerned about flooding the basement?

Signed,

Worried I got burned, but hoping I'm just paranoid...