Changes are not visible
If you make changes to any Host-Party game, you may need to refresh your browser to see these changes in the PrintKit or Invitation. This can include changing to whom the guests on the invite. Most modern browsers have a refresh button o you can usually hit the F5 key to refresh the contents of the pdf file.
Why does this happen?
Some browsers cache pdf documents locally to improve performance. Then the next time you ask for this document they grab the cached version stored on your computer. This is much faster but will not include any recent changes.