How to get Mudanjiang social security card?

A province can only issue one social security card.

After Mudanjiang, Harbin will not work.

You can ask Harbin Social Security Bureau if you can transfer your social security card. This can be done in Xinjiang.

If not, you can only cancel and re-apply in Harbin.

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