About Nanjing insurance.

Social security has nothing to do with hukou. In fact, you have already applied for social security in baixia district, so you can't apply for social security in Jiangning Binjiang Development Zone. You have to go to baixia district Social Security Bureau to issue a payment voucher, and then your company or yourself can handle the social security transfer in Jiangning Binjiang Development Zone. After the transfer, your company can continue to pay social security for you.