Free US Shipping for $35+ isn't working

[juliegarland]

I'm in Canada and have the free US shipping guarantee turned on for my shop so any orders $35+ should ship free. It doesn't seem to be working though as a customer tried to check out with an order over $75 and was being charged shipping. I also tested it with a $90 order in my cart and was also charged shipping to Western New York.

[NanaLetha]

I'm in the US and it works for me. I added 1 item to my cart and can see the shipping charge. I added another to bring over $35 and got free shipping.

[juliegarland]

I just reloaded my cart and the FREE green shipping popped up for my order to the US.  So whatever glitch happened was short-lived!