no explaination

My mom lay byed a phone @ Newtown Junction Pep cell branch. She received a call on tues(8 Dec 2015) that she haven't paid for 2 months for the lay bye. She didn't know that she was suppose to pay every month till she pays it up. She explained that she will take it out Dec but the lady refused & told her she will take it back to the stock. The sales lady never explained to my mom that she should pay every month(4 months) when she made that laybye. Her lay bye is expiring in Jan, now she have to cancel the laybye. This is dissapointing since no one explained to her how it works. Such service is not accepted @ all. Now she can't go to the store to get her money back & when I went to cancel it I was told she should come personally because of signatures. I guess no one cares if she can't make it or not but she has to come personally.