Nescafe K-Cup $1 coupon from samplesource

Provigo and Loblaws has a 5000 points offer WUB Nescafe K-Cups.
It is selling for $15.99 for box of 30.
It would cost $9.99 for the Nescafe Gold with the coupon and points offer.
I tried using it at Provigo and cashier said it was the wrong size.

Coupon says "SAVE on one (1) NESCAFE Coffee Capsules, 9g - 10.5g, any variety"

From the description, the size refers to the weight of each capsule and not how many capsules in a box, but the picture shows a box of 12.

So, can I use this coupon on a box of 30?

I Think you can only use it in a box of 12..