I'm sorry to hear that you had a technical issue that caused multiple charges to be processed when you only bought one item. Please report a billing issue in the Resolution center, so that PayPal can take a look and help resolve the situation.
In a situation where unwanted shipping labels are created, you can void the labels. A label must be voided within 24 hours of creation for UPS or 48 hours for USPS.
I hope this helps!
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