This may be because:
1) You are submitting the Missing Cashback past the 30 days from the purchase date time frame. Please ensure you submit the Missing Cashback request within 30 days of your purchase date.
2) You did not click through ShopBack for that particular purchase. ShopBack takes note of every click you make through to our partner store's pages.
If you have any further queries, please do not hesitate to click here and we will be glad to assist you!