Roseville Supercenter coupon code

I placed a pre-order today on their website and the coupon code " Supercenter " from

last year worked ( $10 off an order over $100 ) , but only on a computer, not a mobile phone.

Don't know why, but I tried code on phone and it said invalid, went to website on computer and

code worked there, I think last year it was the same way.