When you sign in to CRA My Account, do you see your T5s? If you see them in your account and it was not in the Auto-Fill option, please try again, but make sure you won't have doubled T-Slips.
If it's not working, we suggest to contact our product support team. They have access to tools we don't have here in Community, like screenshare, and see the issues to escalate into an investigation if needed.