Moved but still receiving NHI payment forms

Hi, I recently moved from Tokyo to a different city in another prefecture but I'm still receiving payment forms to pay my NHI premiums from Shibuya even though I'm fairly certain I canceled my membership in Shibuya (they took my old insurance card at city hall so that's how I know I should be unenrolled from NHI in Shibuya). I now have a new insurance card from the city I currently live in.

Could this be a mistake perhaps or is this normal? What should I do? I'm guessing I still need to make these payments? Should I call Shibuya's city hall and ask if I'm still in their health insurance system?

Thanks in advance.

Can you check for which month it is that you are charged?
Youfd still be charged for the past month where you were enrolled in the previous NHI.
I believe it is based on where you were gas of the last day of the month,h so if you moved out on May 7th, youfd have been enrolled for the month of April, and youfll get charged for that in June, an example from my municipality says.