Employee Verification

I am a former Dell Employee 1997-2009. I am changing jobs and the company doing the background check is unable to verify my Dell Employment. I have called the nuber givin to me by Dell HR (3rd party vendor) and they do not find a match with my ssn or my dell employee ID. My start date for the new Job is fast aproaching and using the IRS and SSA will take weeks. Hoe do I resolve this issue? is ther a direct nunber with Dell HR I can call to get verification of my Dell employment? Any help with this will be appreciated!