My wife previously had an interview with K-1 visa back in 9/2015 and she received a visa without any issues. However, few months after she arrived US and applied SSN but we have not had a chance to work on AOS, her dad was sick and she rushed back to home before Xmas 2015. Her dad recovered and she was stuck in PH so I submitted the paper work for IR-1/CR-1 Visa. The process also went without a glitch and I credited the good process to her "pre-existing" K1 status.
This time her interview was not approval at the spot due to a not so obvious issue we overlooked. She still has her last name and never registered the marriage in PH.
As a result, her Cenomar, certificate of marriage record, is still showing her marital status is single and with same family last name and so does hers NBI policy report.
She was sent home without a visa and was told to submit those two documents with my last name. So she is still waiting new documents to be sent to embassy (some how without a need to register our US marriage license) and we expect to hear back from them by end of April.
This is something fell through the crack and caught me by surprise. Hope people will not experience same kind of issues in the future.