Bad service cna keywest

I recently went to go and have my volkano bluetooth race series earphones exchanged at cna in keywest shopping centre and they keep saying they dont have stock,it is the end of the month and you dont have stock yet? How long does a person have to wait just to exchange an item,i think its very unorganised from thier side and then they say they do not know when they are getting stock either,so you want to fool me and make me wait until my garuntee is expired? Come on people