a) Dial *#06# on your device to get your IMEI number or go to Settings > About phone to get the IMEI number. Enter the first IMEI number (IMEI1) if there are two IMEI numbers.
b) You can also find your IMEI number on the original package of your OnePlus One device.
a) Please refer to the instructions here: https://forums.oneplus.com/threads/a-journey-from-one-to-10-showcase-your-oldest-oneplus-device.1553711/
a) Find your order number by visiting oneplus.com and going to Your Account > Orders.
a) You may have entered the wrong IMEI or order number. The two numbers must belong to the same OnePlus One device. Please reach out to our support team and provide the correct IMEI and order numbers. A customer support representative will try to help you verify your device manually.
But only once the information you provided are as required and hasn't been verified before can be verified successfully.
b) Another user may have already verified your OnePlus One device. Each device can only be verified once by one account.
c) Your IP may be banned from participating in this campaign for risk control reasons. Please try to submit your information with another account or device in this case.