If you're rejected for a document IRCC claims wasn't submitted, but you have proof it was:
- Submit a Letter of Explanation along with your proof of submission (e.g. screenshots showing the upload). This is the standard first move to contest a factual error in a refusal.
- Be prepared that this doesn't always reverse the decision. Some applicants have gone through this exact process — LOE plus clear proof — and still had the refusal stand, suggesting there isn't a guaranteed appeal path once a rejection like this is issued.
- If the explanation doesn't work, consider creating a new Express Entry profile and reapplying for a future draw rather than pursuing an indefinite dispute — this was the practical path some applicants ultimately took after LOE attempts didn't succeed.
Given the mixed outcomes reported, it's worth trying the LOE route first since it costs little, but plan for the possibility you may need to restart via a new profile.