What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
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I would like to recommend you to delete mentioned subscription form your payment form, if it is still exists.
Then, you may provide your customers with the following subscription cancellation instruction from http://support.google.com/checkout/bin/answer.py?hl=en&answer=1090911
Cancel recurring subscription payments
You can stop your subscription service at any time:
1. Go to https://wallet.google.com/manage and sign in to your Google Wallet account.
2. On the Transactions page, click the View Order link for the subscription you'd like to cancel.
3. Click the Cancel subscription button.
You may also try to contact Google Checkout support for further assistance.
Please feel free to contact us if you have any other questions.