We are aware of an issue causing pages to load incorrectly for some users and expect a fix soon. Sorry for the inconvenience.
Noticing other post. Is this with ProjectLink? I think you need to have all the items shared ahead of time. Can you post screenshots or more details? Exact error messages. See post below for information:
https://www.ptc.com/en/support/article/CS33190?source=search
