Hi ****,
Thank you for writing in.
I agree that you have activated the device on Dec 5th 2018 and have completed the 90 day time period. However, it shows that the device is activated on 2nd January 2019 from our end and that might be due to system glitch.
However, to ensure you are eligible to receive the gift cards, I have also checked with my specialist team about the same. You can expect to receive the gift cards after 3rd April 2019. We apologize for any inconvenience caused due to the delay.