A few minutes ago.
When Scott left, he came back after reaching the gate because he forgot to tell Reina the due date of her deadline to pay back her debt.
While he had told her how much time Reina had left, he didn't tell her the exact date. Even in the contract, only the extra three days after the deadline was mentioned.
To be honest, the entire contract was poorly written, and it was in bad condition. The excuse Scott's family gave was the apocalypse.
Rudy had already realized what they were trying to do. Since Reina's parents were dead, there was no real evidence of what was written in the contract. The original copy was with Scott's family, and Reina's parents were given a duplicate one— which could easily be dismissed in court.
Scott's family was trying to destroy the original contract and create a new one similar to it but on the change of the terms and conditions.