Our living room (18ft * 12ft) had original hardwood floor that has a slope of 3 inch difference across the room. We just put on another layer of new laminate on top of the hardwood floor. Before putting down the laminate, our handyman used many pieces of plywood of different thickness to try to better level the floor (as shown).

However, after laying the laminate, there is a pretty significant dip (as shown) in the location roughly where those extra plywood ends. It's pretty obvious and you can easily feel the dip walking pass it. I am not sure if this is something serious that I should have my handyman come back and re-do it? Any suggestions are really appreciated!