Defect Tshirt from EBucks Shop

I purchased t-shirt online 2 weeks ago and last week Friday I wore it only to discover that the button is damaged. I contacted the eBucks customer care and they informed me of the 7 days no return / exchange policy. No where on the delivery note or the mails I received that this clause was made clear. No reasonable person can know of this clause if its hidden in your terms and conditions. I need my T-shirt exchanged as per the CPA "If the goods do not meet the requirements set out in Section 55, the customer can return them at the supplier’s risk and expense and without penalty. Further, the customer can elect to have the goods repaired, replaced or get a full refund of the original price paid".