Branching to a new discussion,
Sorry to hear that you are unable to cancel your Stock subscription.
Please try to follow the steps as mentioned in the help document Cancel your Adobe Stock membership to understand the workflow better.
I just checked your account details and noticed that you still have 18 assets left which are yet to be downloaded. I would request to download them prior to cancellation since the unused assets will be forfeited after the cancellation of your Stock subscription, however, the assets which are downloaded always remains in the license history.
You may also contact our support team Support FAQ: How can I contact Adobe for support? for cancellation and refund related requests.
If you are unable to reach our support team through the above-mentioned link, please see Contact Support FAQ: Unable to reach support through the "Contact US" link
If you still face difficulties, feel free to update this thread so that we can further assist you.