Legal analysis: unclear authorization means that the authorization of the principal to the agent is unclear. The principal shall bear civil liability to the third party, and the agent shall bear joint liability. The power of attorney shall specify the agent's name, agency matters, authority and time limit, and shall be signed or sealed by the principal.
Legal basis: Article 165 of the Civil Law of People's Republic of China (PRC): If the power of attorney is in written form, the power of attorney shall specify the name, agency matters, authority and duration of the agent, and shall be signed or sealed by the client.