Help

I defaulted on a cash store loan for around $600 back in 2010. Im just wondering what can happen to me because I started receiving phone calls from an Agent Neal, does anyone know who this is? He states that the cash store has decided to file legal charges against me unless I resolve in full. Once I told him I couldn't pay in full only make payments then he said I could make three payments. Once I asked him if he could send me or fax me something showing the arrangement then he said after payments made letter would be sent out. I did let him know I would have to go put money in account for first payment he then asked me to call him when done. I have now called him and left him three messages over three days but he has not returned my calls. Everytime I call him is message says Mr. Neal and not agent Neal I'm starting to wonder if he's legit. Can anyone please give me some advice. Thanks!