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The case and repair ID are different than the serial number. The serial number is 11 characters, numbers or letters. The case number will be 9 digits long, all numbers. And the repair ID is 9 characters. starting with either G, D, or R, and then 8 numbers to follow.

P.S. Are you trying to check your warranty status by chance, and not repair status? Go to here to check warranty status.
 
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