IAPReceiptVerfier returning nil

[ghost]

Hi, I've set up the receipt verifier and it works really well.... 30 percent of the time. I'm testing an auto-renewable subscription purchase in the sandbox and it returns a receipt 30 percent of the time with the correct info, but 70 percent of the time it returns nil. I don't know if this is because I'm in sandbox and if it will work properly when in production, but nevertheless it's frustrating, despite your really impressive work :)

Please fix it or at least get back to me at [email protected] if it's me that has done something wrong thanks :)