GC Services evasive, untruthful, not forthcoming on any details, unwilling to commit to anything in writing Internet, Internet

The individuals at GC Services (which appear to be New Hampshire-based, given the 603 area code) have been harassing me with vague and impossible-to-understand telephone calls for approximately 4-6 months now.  I am in the process of repaying a student loan through Xpress Loan Servicing, a Chicago-based company. 

Without ever providing any written documentation or explanations as to their role in any of this, GC Services has suddenly taken to calling me multiple times a day with statements to the effect that there in fact two loans (not true), and that they are the rightful recipients of monthly repayments.  There are also poorly-worded threats of wage garnishment, insistence that there are in fact TWO loans (not true), and most pointedly, an obstinate refusal to acknowledge the existence of Xpress Loan Servicing. 

I have taken to ignoring their regular phone calls and continued to make my monthly repayments to Xpress Loan Servicing, for which there is adequate documentation and monthly statements.  On the few occasions I have dealt with an in-person individual at GC Services, there has been little to no cooperation, a consistent refusal to acknowledge my relationship with Xpress Loan Servicing (GC claims to have never heard of this organization), and repeated promises to provide detailed written explanations as to their role in all of this.  I have verified that GC Services does indeed have my correct mailing address but I have yet to see a single document from them. 

This frankly smacks of middleman-skimming and I will continue to ignore them, making my monthly repayments to Xpress Loan Servicing.