The social security I bought in other places has not been transferred back to my hometown. Can I buy a new one?

If your account does not move with your job, you can re-open an account in other places and pay social security according to local policies. You can also ask your current unit to help you deposit money in your hometown, but you need to entrust other professional companies to handle it on your behalf.

According to the current policy, your social security account cannot be transferred from your hometown to other provinces, but only from other provinces to your hometown.

If your account has been moved to other places, you'd better re-open it locally and transfer the original social security.

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