Why did the status bars on Where's My Refund disappear?

If the refund status bars on WMR disappear or reset to 'Return Received,' your return may be under additional review. This can happen due to identity verification needs, errors in your return, credits being verified (EITC/ACTC), or random compliance review. It does not necessarily mean something is wrong. Wait 21 days for e-file or 6 weeks for paper returns before calling the IRS.