Du brauchst nur zu deinem zustaendigen SSA-Office gehen und dann bekommst du auch eine neue Card (Nr. bleibt gleich).
How do I get a number and card?
You must complete an Application for a Social Security Card (Form SS-5). To get an application:
Go to
www.socialsecurity.gov/online/ss-5.html on the Internet; or
Call 1-800-772-1213; or
Visit a local Social Security office.
To get a Social Security card, you must provide original documents that show your age, identity and citizenship or lawful noncitizen status. We verify birth documents for U.S. citizens age 1 and older with the office that issued the documents. We verify Department of Homeland Security (DHS) documents for all noncitizens with DHS. You will get your number and card as soon as we have all of your information and your documents are verified.
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Types of cards
We issue three types of Social Security cards. All cards show your name and Social Security number.
*The first type of card shows your name and Social Security number and lets you work without restriction. We issue it to:
U.S. citizens; and
People lawfully admitted to the United States with permanent DHS work authorization.
*The second type of card shows your name and number and notes, “VALID FOR WORK ONLY WITH DHS AUTHORIZATION.” We issue this type of card to people lawfully admitted to the United States on a temporary basis who have DHS authorization to work.
*The third type of card shows your name and number and notes, “NOT VALID FOR EMPLOYMENT.” We issue it to people:
From other countries lawfully admitted to the United States without work authorization from DHS, but with a valid nonwork reason for needing a Social Security number; and
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What if my immigration status or citizenship changed?
If your immigration status changed or you became a U.S. citizen, you should tell Social Security so your records can be updated. To get your immigration status or citizenship corrected, you need to show documents that prove your new status or citizenship.
http://www.ssa.gov/pubs/10002.html
Gruss
Michael