If you cannot get discount,
please check below reasons:
A limited amount of discounts are available.
Distributed on a first come, first served basis, you may not get discount
when it is out of stock.
Check the deadline of discount. As we always have
various activities on DX, you can join other activities to get coupons and
Check if you meet the minimum spending requirements.
For example, if it shows "US $5.00 off per US $50.00", it means
you can get the US $5 discount only when your order value is over US $50.