Attachment from Calendar invite removed?

When i create an invite to a calendar item and attach a file (PDF in this instance) it is not there anymore after a short amount of time.

Hello Christian,
what version of eM Client are you currently running? Check the Help>About section for full version number.
What calendar account does this happen on? Is it a Google Calendar/iCloud/other?


This is on an account

version is latest at date (updated this morning)

All our Users have the same problem. We are using Google for Work.