Hunan Hengdong endowment insurance is paid in one lump sum.

Now it seems that you can transfer the part you handed in to the enterprise in Hengdong. You need to work in the enterprise here and get it from the Social Security Bureau in Hengdong. Specifically, you ask Hengdong Social Security Bureau.

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