Is the IOU written by the creditor and signed by the debtor legally effective? What if the creditor modifies the amount privately?

Hello, the debtor's signature shows that he is responsible for approving the contents of the IOU. Of course, if the debtor can prove that the signature is forced or that the meaning is not free or misunderstood, then the IOU can be revoked by the court. If the creditor modifies the amount of the loan without permission, you can refuse to admit it, and let the other party bring a lawsuit to the court, and then you can apply for verification that the handwriting was added later.

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