Can you help me ask where tongshan district residents' medical insurance is?

I suggest you take the medical insurance card to the social security bureau window and ask if you can return it. If you can, then your medical insurance card can continue to be used. If it cannot be returned and the interruption time is too long, it is invalid. Can you make another one and treat it as reinsurance? The medical insurance cost for urban residents is not high. At least there is a guarantee. Nobody can avoid getting sick or something.

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