Background check job history verification

This is my first time having to do a background check that involves verifying employment dates. I accepted a job offer and they require this before I start in 2 weeks. I provided them with HR numbers I am a little nervous what if the numbers aren’t right or they can’t verify me. I couldn’t find the HR to one of the jobs I had 3 years ago. Will they be able to find it ? I only put down 4 jobs. I would really hate for my process to be delayed due to not being able to be verified. I’ve heard people not being able to be verified and have to get W2s or pay stubs. It’s with a company called Sterling Talent. They said only need to verify my employment dates.

Am I just freaking out ?

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