Debt Collector help

I starting recieving calls from a company called NES out of Ohio in regards to student loans I had co signed on for my daughter. They called me at work and I told them I would call them back, I wasn't able to call them back that nite. The next day my husband called me to say his old boss called him stating he got a call from this guy(the one who called me) and said that my husband and I were in negotations with him and he needed to speak to my husband. My husband called back the number and the man started saying he was gonna take me to court and etc. etc. if we didn't come to a settlement with him to pay off the student loans. My husband told him, he wasn't on the loans and didn't know anything about them. He would have to talk to me and hung up. Half hour later another man called trying to get him to come to an agreement for 70,000 to pay off the student loans. First off was that legal, for them to contact my husband..and second I have been trying to work out a payment plan with them and they keep telling me I have to pay a large sum just to go on a payment plan and when I tell them I don't have that kind of money they will put me on hold until I hang up...Is this a scam? I didn't agree to anything or sign anything. The only thing I did wrong was give them my account number, for when we did agree on a payment plan. Any advise would be great...:confused: I don't want to deal with this people but I do want to straighten this out...