Why does onboarding say my Tax ID is invalid?

Last updated: September 14, 2026

Applies to: Workers being onboarded through Ascen who hit an "Invalid Tax ID" error, most often people who have picked up work through more than one app or staffing agency. It is not about your Social Security number being wrong.

Summary: The most common cause is that you already have an Ascen profile from a different app or agency you have worked through before. When a second profile is created, our system recognises your details on the existing one and stops the new one with an "Invalid Tax ID" message. The fix is on our side. Email support@ascen.com, tell us which app or agency you are continuing with, and we will connect your records so you can finish onboarding.

Why this happens

Several apps and staffing agencies use Ascen as the employer behind the scenes. If you worked through one of them before and you are now starting with another, that second company creates a new profile for you — but your tax details already exist under the first one. Rather than creating a duplicate record, the platform stops and shows an error.

The message names your Tax ID, which makes it look like you typed your Social Security number wrong. In this situation you almost certainly did not. Re-entering it, or entering a different number, will not clear the error — and you should never put anything other than your own correct number on a tax form.

How to get it fixed

Email support@ascen.com with:

  • your full name and the email address you are onboarding with;

  • which app or agency you want to continue with — this is the one thing we cannot work out for you;

  • the name of any other app or agency you have worked through with Ascen before, if you know it;

  • a screenshot of the error.

We will connect your records and confirm when you can carry on. Then log back in at app.ascen.com/login and continue where you left off.

What happens to your existing information

Connecting your records is designed to keep what you have already done, so you should not have to redo your whole onboarding. Your pay history and your bank details stay with you, and in many cases a Form I-9 you have already completed and had verified does not need to be done again.

Occasionally a step does have to be repeated — for example, if a previous Form I-9 was never fully completed. If that applies to you we will tell you which step to redo, and the rest of your onboarding will carry over.

What not to do

  • Do not create another account with a different email address. That adds a third profile and makes it slower to sort out.

  • Do not change the number on your tax form to something that is not yours.

  • Do not keep retrying the step — the error will not clear by itself, because the fix is on our side.

If that is not your situation

If you have never worked through another app or agency using Ascen, then check that the name on your profile exactly matches your Social Security card and that your number was entered without dashes or spaces. If it still fails, send us a screenshot and we will look at your record.

Who to contact

  • Ascen (support@ascen.com) — the Invalid Tax ID error, connecting duplicate profiles, tax forms, and account access.

  • The app or agency that hired you — your shifts, your schedule, and your assignment.

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