thm1010

I have a percentage off sale. I'm giving 20% off a certain type of item. But, when you check out, it's giving 20% off the total including tax and shipping. I set it up in the coupon/voucher section. What I am I doing wrong? I only want 20% off the items - not shipping and tax. Please let me know how I can fix this. I have sales coming up all month.