The difference between regional social security and provincial social security

If the provincial social security and the "municipal social security" you mentioned belong to the same provincial administrative division, there is no difference, because now the social security policy is localized management and provincial overall planning. In the same provincial administrative division, retirement benefits are coordinated by the same policy, and there will be no difference, unless your city belongs to the national "city with separate plans" and has its own independent social security policy.

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