Ну, например, так - не помню слово в слово, как писала сама, черновик не сохраняла 

 Обращайтесь, если что - переведу. 
Dear 6pm team, 
I have earned about ... (число ваших баллов, хотя бы примерно) Brandaholic points and have been waiting for the promised 10% codes for really a long time. Unfortunately, I haven't got any coupone code yet. 
I would really appreciate if you could send me those codes as I do need them to continue shopping with 6pm.
Looking forward to your positive response, I remain your loyal customer.
Faithfully yours,
(Имя)