An imported audience is not a guarantee that every row is sendable. Check the import result, selected audience, number format, and any duplicate or suppressed entries. A recipient's saved profile also does not establish marketing consent.
Compare the campaign's recipient results with the intended audience before importing the file again. Identify a redacted example and the reason shown for its exclusion. If those disagree, report the import and campaign references to support. Do not attach the entire customer list when a small reviewed example explains the problem.