Payment errors

• My customer's cards keep getting declined. What do I do?
• What does an insufficient funds error mean?
• Why was a payment blocked?
• What does "This transaction requires chip and PIN" mean?
• What does "Your card does not support this type of purchase" mean?
• What does "declined for making repeated attempts too frequently or exceeding its amount limit" mean?
• My customer's card needs a ZIP code, but there's no field to enter it
• Why a payment shows "Incomplete" in my Stripe Dashboard