Creating a note from a calendar event - duplicates and missed notes

Hi!

Last year I cobbled together a shortcut to automatically create a note from my (work) calendar entries.

Workflow background idea: If I have a meeting in the future, I can a) check what meetings are coming up and add notes as a preview, I have a place to add notes when Emails for a future meeting come in, and I can go through all meeting notes once done, work through them and do what needs to be done with the info.

I have this shortcut automatically run on my iPhone every morning at 4am. Notes and calendar are on MS Exchange (work). Problem persists when using iCloud notes.

Problem I have encountered: Some notes are created every time the shortcut runs. Some notes are only created once. Some notes are not created at all, although the event is in the calendar.

Any ideas what may be going wrong? Thanks in advance for any tips, either for the shortcuts or workarounds/changes in my workflow.