Always use the mail not the phone to resolve these matters. I use to work at a credit bureau about 10 years ago so things could have changed. However. You write to ALL three credit agencies and be very specific in your letters.
Include who are disputing who what where and why. Also include that you are in the process of seeking legal representation because of this situation. Because we were trained that anything that said "lawyer" or anything from a law office was forwarded to a different dept. for different handling.
Further which may help, sometimes credit report companies may remove a dispute or correct to your favor a certain dispute, WAIT for it to come back to you. If agency A makes a correction, then make PHOTOCOPIES of their FINDINGS and CORRECTIONS and MAIL to agency B and C with a letter stating that you are disputing this and based on so and so credit agency (one of the big 3) they found it in error and corrected and you are seeking to have it corrected with their agency.
USUALLY they will just correct it rather research themselves. I had to do this myself to get my credit report corrected to buy our first house.
Also you want to consider WRITING a letter to the company itself outlining your problem and that you are thinking about contacting a lawyer and ASK them to correct the error and report their correction to the said credit agency.
Use those "magic erasers" I would use the name brand toughest strength for those. My daughter had these black boots that made bad rubber marks on the kitchen floor, the magic erasers worked like magic!
You can use goof off product, but it does leave an oily residue some make sure to use a soap/water solution to get rid of the goof off. ... View related article.