This happened to me, too, the first time I tried.

I had to empty my shopping cart, log out, log back in, select one item, go to cart, add free shipping coupon, update cart, continue shopping, add another item, then add the $20 coupon.

May work in other combos, but this is what worked for me.

I've worked with their cust support on a similar problem in the past. They just pulled up my cart and applied the coupon that wouldn't work for me on-line.

Hope this helps!

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