Client on ITC for a PAID account

I was sent an account in January 2016 for tests done in hospital in September 2015. Apparently the account was rejected by our medical aid.<br> <br> I sent the account through to our medical aid and 5 days later (22 Jan 2016) the account was paid.<br> <br> Today I was notified that the account was handed over to ITC and that after it was paid in full!!<br> <br> ITC has the audacity to tell me that the extra costs is for admin fee and I have to pay it. Basically I have to pay for Lancet's slip up and above all, receive a bad credit rating for it???<br> <br> I phoned Lancet and they promised to rectify it immediately and email me the proof that it has been rectified. 3 hours later, no mail received. <br> <br> This is totally UNACCEPTABLE! You're ruining peoples credit records for nothing!!!!!