refuse of the refund

I bought the tab Samsung galaxy from gug gug in maponya mall.my son did not like it and when I return it for the refund they told me the policy does not allow.Note that i was given a slip with a stamp at the back with that policy which is not readable .ji was just told that it's only returnable within seven days.I bought it on the 7th December and return it on the 10th December 2015.I left the tap 4 sung sum at the shop<br>