"I have read the sales agreement."

Which sales agreement? There should be Two:

Real Estate between some parties, and we don't know who sold real estate.

Business assets, liability, inventory, AR, AP, broken out, and between the Partnership as seller and some other party.

"Total price 720,000.00"

Total price, for what?

If you read this topic from the beginning, you would review how certain sales cannot be sold by the partnership, others cannot be sold by the individuals, other components do not qualify for being handled as an installment sale (and what you seem to factually have is two individuals acting as lenders, perhaps).

You need to identify each component, break down who was the rightful owner, then confirm if any associated paperwork reflects these facts or was prepared in error.

No one here can even confirm if the 1065 has any of this activity on it correctly. The mistakes may have been made before anything was handed to you.