Hi @Snoopans,
Could you please share a screenshot of your flow's configuration?
Did not your flow be triggered at Saturday and Sunday?
Further, could you please show a bit more about the issue that you mentioned?
I have made a test on my side and don't have the issue that you mentioned. Please check if there are some events start at Saturday and Sunday last week within your Outlook calendar.
In addition, please check if the connection to the "When an upcoming event is starting soon" trigger is invalid, if yes, please update the connection to the trigger and try your flow again to check if the issue is solved.
Best regards,
Kris