After buying Hair an...

After buying Hair and and as I stepped out of the shop realising I bought wrong, I went back in witch was Literally 2min to exchange it.. but I was denied due to the policy procedure they have. However I find it very inhuman for the fact that I bought it at 13:46 and I was back in the shop 13:49, meaning I didn't even get far with it but still I wasn't assisted.. I even told the manager that this is an honest mistake but he just told me about their policy, I feel that they are not considered for their customers.