Hello,
To keep syncing with the AnKing Deck from AnkiHub and continue to receive updates, you need a paid membership. However, you do not need a membership to sync between devices and back up your collection to the cloud using AnkiWeb (the Anki sync service).
The AnkiHub add-on tries to sync whenever you click the main sync button in Anki. If you are no longer using AnkiHub, you can disable or delete the add-on to prevent this. Simply go to Tools > Add-ons on your Anki main screen, select the AnkiHub add-on from the list, and click Toggle Enabled or Delete.
This is the Anki sync button:
Let me know if you need help with anything else! 