A modification of a contract is a change in an obligation by a modifying agreement.

A contract not in writing may be modified in any respect by consent of the parties, in writing, without new consideration, or by oral consent of the parties with new consideration.

A contract in writing may be modified by a contract in writing or by a fully performed oral agreement. [An oral agreement is fully performed whenever the party performing has incurred a detriment, which such party was not obligated by the original contract to incur.]

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