Hello,
I am having what may be a similar issue.
When some events are deleted or rescheduled this can effect my Fastmail calendar but won't affect a Google calendar that is linked to my Fastmail calendar.
And, Fastmail calendars are shared with Google calendar in a way that makes it impossible, at least some times, to delete the event in Google calendar.
I’ve been unsuccessful getting Fastmail support to resolve this, so far.
|