Why does one of my purchases cashback "unconfirmed"?

Major causes of the purchase cashback unconfirmed are listed as below:

*Cash Back of some merchants posts after order delivery is confirmed. 

*Many travel companies make the cash back conditional upon you completing the travel reservation. Once the travel has been completed, they will update your account and post the cash back for your order after that date,usually within 1-2 months.

*Cash Back is not eligible on selected goods.

Thank you for your patience.