If you do not want a connection to be active anymore, you can delete it using Meld's delete connections endpoint. Once you delete a connection, it will be deleted on both Meld and the Service Provider's ends, and you will no longer receive any updates (through webhooks) regarding it, as well as no longer be charged for it. You can only delete a connection, not the link to any individual financial accounts associated with the connection.

How to Delete a Connection