The mnemonic is encrypted and stored on the user's mobile phone, not on any centralized server.
In order to maintain the security of users' assets, UUwallet does not provide centralized services, including "retrieval of lost private key", "retrieval of encrypted password", "freeze account", "rollback transaction", etc., which also adheres to the decentralization of the blockchain characteristics.
Therefore, users need to keep the mnemonic phrase and password properly, and UUwallet cannot help you retrieve the mnemonic phrase.