Dont want to refund an item

I bought an item on Wednesday, 13 April 2016. On the same day I wanted to return it, because it was not fitting and with the return it was and is in good condition, but the Store Employee told me that they do not have enough money to refund me and that I must come back today. Today I when there again and now they say they can not refund me anymore. I called the store to talk to the Manager but they say she's not there. I asked my Secretary (white lady) to call them and ask for the Manager. As soon as she asked they gave the Manager the phone. When the call was transferred to me I noticed that the Manager talking was the same lady who said the Manager ant there. It is very poor the give such assistance. It is inappropriate and unacceptable.