Sears Solution Mastercard Household Bank One year deferred interest on purchase is deceptive advertising Internet

I had to purchase a washer and dryer; which was a rather large purchase for me and so I signed up for the sears solutions mastercard with one year deferred interest charges.  As part of the process, I signed up for online banking to save a tree.  They told me that as long as I paid the principal balance off within the 12 month time frame, I would not be charged interest. A few months ago, my lawnmower broke and I purchased a lawnmower from Sears on the same card.  When I purchased the lawnmower I asked if this would affect the remainder of my deferred interest on the washer and dryer and was told no, that as long as I paid off the remaining principal due by the deadline I would not be charged interest on that purchase.  That the principal payments I was making would go towards the oldest charge first.  Imagine my surprise when I paid off the purchase in full by the deadline and was still assessed deferred interest charges.  After calling and being disconnected three times and spending over an hour of my time trying to get this resolved, I was finally connected to a representative and then a mangager who explained to me that the reason why I was assessed deferred interest was because they applied part of my monthly principal payments against the newer purchase.  When I said that was in conflict with what the store had told me, I was told they have no control over what the store told me and that they can apply the payment that way.  Apparently there is a link to a page on their online statement that explains this and that I should have known to go find that page and read it so I would know that my payments were not being applied the way I had been told they would be. People who receive paper statements receive this with their statement, but online customers do not. I was told it is my responsibility to read every link on their page every month to make sure I understand how they are applying my payments.  If you ever sign up for this program with Sears, DO NOT EVER buy anything on that card again, or they will screw you too.  Their program is set up to ensure that all customers who use the card again are forced to pay the deferred interest charges.  It is deceptive and misleading.