RETURN POLICY?

Hi! so my story started when i purchased a watch from my collage batch mate. I bought Beverly Hills Polo Club Watch worth 5000. Then hindi ko siya na check agad kasi i was with my bf na pagbbgyan ko ng watch. Then when i went home I checked it and then this "made in China" thing at the back of the watch made me skeptic if it was authentic. Since i don't know what to do at first i ask opinions from my friends then i went to the mall (watch store) and they said it's fake. So i told my bm(batch mate) about it she said she can guarantee me its authentic. I was not convinced so i also went some watch stores at Market2 and SM Fairview and none of gave the idea that it's authentic. so I told my bm that i want my money back.She said they're willing to give it back. Na offend siya dahil ako lng daw nag sabi na fake ung items niya. I didn't mind ksi ang gusto ko lng mabalik ung pera ko kasi hindi worth ng nabili ko. She passed the problem to her business partner. Ayun we made an agreement that on July 01,2013 ibabalik nya ung pera ko. On my way bigla niya sinabi na chnage item na lang ang option dahil hindi daw pumayag ung supplier na ibalik yung pera ko. I told her na ayoko ng items nila gsto ko ung pera ko. But i had no choice kasi kahit anong galit ko hindi nila mbbgya ung 5000 ko that day. so i gave them their watch and i am still waiting for the money. Pero pnipilit ko pa rin na ibalik na nila ung pera ko since i am still thinking na problem nila un with me not with their supplier.

i need legal advice