If your credit report reflects that a reinvestigation is under way, this indicates that the credit bureau whose report you're reviewing is currently in the process of attempting to validate the disputed information. Contrary to how it sounds, a reinvestigation is actually the initial investigation that follows a dispute.
The FCRA gives each credit bureau 30 days to conduct its reinvestigation. If the information provider can't validate the information or fails to do so within the 30-day time frame, the credit bureaus removes the disputed item from your credit report.
The credit bureaus use a program known as e-OSCAR when validating disputed information. e-OSCAR allows each credit bureau to forward your dispute directly from its computer system to the information provider's computer system and compare data. Unfortunately, if the inaccurate information is still on file with the information provider when the reinvestigation takes place, e-OSCAR validates the incorrect data as accurate, and the credit bureaus don't remedy the error.
The FCRA doesn't restrict you to disputing incorrect information with the credit bureaus. You can file a dispute directly with the information provider that originally made the inaccurate report. Like the credit bureaus, the information provider has 30 days in which to investigate your claim. The information provider must then supply the results of its investigation to the credit bureaus --- who must then modify your credit reports to reflect the corrected data.
If an initial reinvestigation results in an information provider verifying incorrect information, you have the right to file a second dispute with the credit bureaus. You don't, however, have the right to a second reinvestigation.
If you provide new documentation supporting your claim or dispute the entry for a different reason, it's at the credit bureau's discretion whether or not to attempt to validate the data a second time. The FCRA also grants the credit bureaus the right to determine that any further disputes you submit are "frivolous." Once a credit bureau marks a dispute as frivolous, the law no longer requires it to investigate the validity of your claim.