Home inspection shows a cut joist.
The best advice is to spend a couple hundred bucks and hire an engineer to design a proper fix for the joist, but yes, it can be fixed. More often than not it'll involve adding a sister joist of the same size to one or both sides of the damaged joist. Lots of construction adhesive, lots of nails (not deck screws or drywall screws). The best advice is to sister the full length of the joist, but it may be possible to use a shorter piece with the proper engineering.