How do I change the amount on my PayPal payment field?

How to a change the amount for my deposit? If I customize it before sending with it effect previously sent documents?

I am not sure if I understand your query correctly. Do you have any payment method integrated on the form and you want to change the pricing configured on it? If so, you may access the payment wizard and change the pricing set for the product/subscription. In this case, the previously received submissions will not be affected. 

Let us know if you are referring something different. We will be happy to assist. 

Yes, and I went into the wizard and it's not letting me change it
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Hello,

I can't seem to find a form that has a payment gateway field in it. Can you please share with us the form that you are working on so we can have a look on what's going on?

Thanks.