DuplicateContract

Instantiation would create a contract at an address already occupied by an existing contract. Check the derived contract address and vary the salt argument to obtain a fresh address.

Declared by the Contracts pallet; it classifies to the semantic code already_exists.

Remediation

The object or state already exists; treat the goal as met or pick a different target

The same explanation is available in the terminal: btcli explain DuplicateContract.