Form I-129F, Petition for Fiancé
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
Thin proof of meeting in person — one photo is not a record
Missing intent-to-marry statements from either side
Assuming the K-1 works for a couple already married — that is a spouse case, not a fiancé case
Forgetting the consular stage: the DS-160 and interview follow the petition
Form I-129F
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