If you click on a Dynamic Forms link and get the error message "Authentication information needed. Please contact your school", please try this:
Copy the whole link and paste the link in your browser.
Dynamic Forms links need a prefix link added to the regular form link to allow people to log in with their Lesley credentials. Sometimes when someone clicks on a link in an email, only the 2nd half of the link goes into the browser, which causes the link to fail. Copying the whole link fixes the issue.