How do I reverse the money after canceling subscription

Apple must first approve your refund request.

After that, the amount will be refunded to your account by Apple.

See this Apple article: 

Check the status of a refund for apps or content that you bought from Apple

Check the status of a refund for apps or content that you bought from Apple – Apple Support (UK)

If you canceled in time, the money won’t be sent. See especially the “If you signed up …” sentence near the end here.

How to cancel a subscription from Apple - Apple Support