UpCharge Fees Addons Surcharge

UPDATE:
working with customer service they were able to help me with my issue super quick which is dope, so I am happy now. Careful if you get Angie as a rep though she's got a bit of sass and will talk down to you, but other than that, it's good. ORIGINAL:
Be careful, this app could stop your add to cart button from working. Support cannot even figure out why, so I'm literally sitting here losing sales.