If the PR tracker registration keeps failing after submission, the likely cause is a temporary UCI that hasn't been replaced with your permanent one yet.
What group members advised:- Right after submission you're issued a temporary UCI starting with 'CAN', which needs to be replaced by your original/permanent UCI (the one that matches your prior work permit) before the PR tracker will work.
- This replacement typically takes about 24–48 hours, and even after it updates in the GC Key portal, you should allow another ~48 hours before the tracker registration will succeed.
Takeaway: if your PR tracker registration is failing shortly after submission, it's likely just a timing issue with your UCI updating — wait a few days and try again rather than assuming something is wrong with your application.