How to resolve delayed Apple Gift Card payment from Likewize for iPhone trade-in?

Sent iphone to Likewize for Trade in via Apple. They accepted the device and agreed the amount to be paid on an apple giftcard, that was on the 20th May, over 3 weeks ago and still not received apple giftcard. Likewize suggest the delay is with Apple and not them, not sure where to go?

[Re-Titled by Moderator]

Original Title: Likewize payment issue