Legal analysis: the power of attorney generally determines the effective time according to the nature of the entrusted matter. According to the principle of agency by estoppel, if a person is entrusted with the same thing for many years, as long as the entrusting party does not notify the other party in writing, the entrustment is regarded as long-term effective. The term of validity of the power of attorney shall be subject to the agreement of both parties in the power of attorney, and both parties shall freely agree according to the entrusted matters. If there is no agreement or the agreement is unclear, it can be regarded as the termination of the entrusted matter on the date of completion. Power of attorney is to entrust others to exercise their legitimate rights and interests on their behalf, and the client needs to show his legal documents when exercising his power.
Legal basis: Article 934 of the Civil Law: If the principal dies or terminates, or the agent dies or loses capacity for civil conduct or terminates, the entrustment contract shall be terminated; However, unless otherwise agreed by the parties or due to the nature of the entrusted affairs, it is not appropriate to terminate.