Work from the documents outward. Collect every refusal letter, notice, passport stamp and prior application, sort them by date, and write your recollection beside each. Where they conflict, investigate and explain the discrepancy; an official record may itself contain an error, so do not replace the truth with a document you know is inaccurate. The gaps you cannot document are the ones to resolve before filing.
Building a dated file the answers can rest on
Start with the application submission and decision dates, then investigate the disputed facts, then attach the underlying document to each line. Where nothing survives, note the gap rather than guessing a date to fill it. The same file later supports the I-140G stage, where supporting documents go through the official portal, and again at interview, where additional documents are requested.
Build the chronology once and keep it current, dating each revision. The same file is consulted at several stages separated by months, and a version that has quietly changed between them creates the very inconsistency it was meant to prevent. When a new document arrives, add it with the date received rather than folding it silently into an earlier entry.
Where a record is requested and never produced, keep both the request and the acknowledgement; an unanswered enquiry with a date on it evidences an attempt, whereas an unexplained blank does not.