Payment info

I was duplicating one of my forms and making some changes.  Now when people register it either does nothing after you push the submit button or say payment info is wrong.  Its been so long that I don't know how this was set up.  How do i fix this problem?  I can't even find the page that says how to link my PayPal account.  

Did you integrate your cloned form with your PayPal account? 

How to Integrate Form with Paypal (Standard)

Please check if the form is integrated with your account. 

If the issue still persists, provide us a link of your form.