I emailed JetBlue and Barclay. JetBlue responded with the following:
Thank you for contacting JetBlue. When you use your JetBlue Card during a flight, the full charge is collected initially and your discount is applied after the transaction posts to your account. Cardmembers qualify for a 50 percent discount on cocktails, food and other eligible purchases. Duty-free purchases do not qualify.
Savings will appear as a statement credit four to six weeks after the transaction posts to your account. If you do not see the adjustment on your statement within that time, please contact Barclay MasterCard directly at 1-866-928-3104.
We apologize for the inoperable TV's on your last two flights home. If you did not receive your $15 credit for these flights, please let us know and we will be happy to apply the credits to your Travel Bank accounts.
Christopher, thank you for choosing JetBlue for your travel needs. We appreciate you as a JetBlue customer! It will be our pleasure to welcome you onboard with us again in the near future.
Sincerely,
Nan
JetBlue Customer Commitment
Crewmember 86263