Is it possible to change the amount to be charged later using Square payments?

Hi there,
I didn’t mean to set time, but rather set the amount. Just because the amount we charge varies based on what services a family uses them, and how long. Or say if a family cancels and we need to charge a cancellation fee, will we be able to specify the amount that we are charging to the card saved?
Thank you again.
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I am trying to test the feature of Authorization only and it seems that it is still in the development mode. Could you check if this option is available in the payment wizard for your form? I have checked it on my test Free account and was not able to find this option. However, it is displaying in my account.

To answer your question, I believe that JotForm can send the authorization information to Square payment and it can be billed only once. I am not sure if there is an option within Square dashboard to charge the customer later and again using the same card. Since the Test transactions cannot be displayed on Square dashboard at the moment, I am unable to test it. We request you to check with the Square support to see if they can provide any further information in this regard. 

Thanks!