The insured of the dividend insurance policy does not sign in person, but authorizes others to act as agents, and the contract will take effect.

Article 13 of the Insurance Law stipulates that an insurance contract is formed when the applicant requests insurance and the insurer agrees to underwrite it.

According to the law, civil acts can generally be authorized by others, or I ratify them afterwards, and the contract is valid.

Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.