Credit Score Report Errors Costing Big Bucks our consumer watchdog report and a growing problem. Americans and their credit scores taking a dive. And sometimes it's not your fault. Tonight paula faris with one woman trying to fight back. Reporter: They're the credit reports that can make or break a loan. This week we learned those reports have errors that could keep us from getting a car loan, a mortgage, even a job. A new study uncovered one in five americans have mistakes on their credit report and over four million of us have mistakes that can lower our credit score. It's very important that this information be accurate, so that consumers are not harmed by inaccurate information. Reporter: That's exactly what happened to renee from ohio, who unsuccessfully battled the credit bureaus for three years over a mortgage discrepancy. She says her credit rating was destroyed. And her and her family couldn't buy a new home. I had good credit. I worked hard for it. Then I had to watch the whole thing fall apart. Reporter: We reached out to the big three credit bureaus and they told us to talk to this man. Credit bureaus want to get it right in the first place. These consumers are their customers. Reporter: So can you fix your score? It's possible, but time consuming. Check your report at least once a year. Go to annual credit report.Com. It's a government-run site. You can print your report for free. Go through line by line and write down any errors. Finally, gather proof and contact each of the three credit bureaus. By law, they have 30 days to respond. If they don't, go to the spc or our state's attorney general. Renee has had to rebuild her credit, but it's been a painful lesson. What I figured out, you're at the mercy of the credit bureau. What a nightmare for renee. You said she caught it, but caught it too late? They tell me, if you get nowhere, contact them directly. They're policing these agents more now than ever. In the meantime, you made calls for renee, will they look at her report again? They said they would and they'd get back to us.