I have members pay for a subscription to my NING site with one option being to pay $90 for a year subscription. The payment is processed through Stripe. However I just went into Stripe and noticed an unexpected "NING application fee" of $4.50 per subscriber in addition to the Stripe $2.91 credit card processing fee (which I did anticipate). How do I turn off the NING application fee? It came as a big surprise to see this NING fee for my subscribers on top of the monthly fee I already pay for NING services.