The social security number that you submitted is not recognized. if you mis-keyed it, correct it and re-submit your registration. if your number is correct, then it is not yet in our database and you may not register online. therefore, you will need to send your registration by mail.

The social security number is your identity in the US. And if you enter it, and it shows invalid, it can only mean you are not registered. Hence, you need to go to the site mentioned in the explanation and create a new social security account. If in case you have lost the social security card, and you have forgotten and that is why it is showing the wrong SSN, then you can opt for the replacement card.

In some states, the replacement card facility is not being provided, and those are being listed on the site mentioned in the explanation.

Explanation:

The site for creating a new SSN account or apply for a replacement card is as below:

https://www.ssa.gov/myaccount/replacement-card.html

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Explanation: