Form I-131, Travel Document
The same few things, over and over — and every one of them is a completeness problem the software checks for before your packet is marked ready.
Watch for
Leaving before advance parole is approved — that can abandon a pending green card application
Checking the wrong document type
Filing a re-entry permit from abroad — you must be in the U.S. when you file
Confusing the travel document with the work permit; they are separate applications
Form I-131
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