If there is a conflict between the chat record and the contract, which one shall prevail?

Look at the time sequence of chat records and contracts.

Chat records come first, and contracts come last. The contract shall prevail.

Chat records come last, and contracts come first. See if there is a clear agreement in the contract to change the contents of the contract. If the agreement must be changed in writing, the contract shall prevail; If the agreement is oral, the chat record shall be regarded as a contract change, and the chat record shall prevail.