If you click on the link in the email and are not logged in there are a couple of things you can check:
Submitted the form more than once
If you submitted the form with your email address more than once:
Make sure you clicked the link in the most recent email you received.
Each time you submit the form the previous link that was generated will stop working.
If you use a program like Microsoft Safe Links
What's happening:
Microsoft may be requesting the URL before you visit it.
This request will process the link at which point it can't be used again.
When Microsoft finally directs you to the link it is no longer valid.
What you can do:
Right-click on the link in the email
Copy it
Manually paste it into a web browser.
It should then work.