La. Civ. Code art. 3031
Current with changes from the 2024 legislative session effective on or before 7/1/2024, from Acts 2,3, 6-535, and 580-647
If the mandatary does not know that the mandate or his authority has terminated and enters into a contract with a third person who is in good faith, the contract is enforceable.
La. C.C. § 3031