Thank you for posting question to Microsoft Q&A forum.
First, have you tried to cancel the original series in Teams where you created the series?
What is your subscription? (M365 Business Standard, Premium, E3, E5, etc.)
You mentioned you forwarded the meeting; did you forward the meeting to yourself or to someone else?
Please verify if my understanding is correct.
You created a meeting series in Teams, but it was not sync to Outlook Classic calendar.
Then you forwarded that meeting series to yourself, and you clicked accept it.
Result in like screenshot 2, Organizer still shows your name, but you cannot find Cannel meeting button. This issue most likely because the sync error between Teams and Outlook.
If you cannot delete the meeting in Teams, then please reach out to your IT admin, they will be able to remove it with PowerShell commands. Remove-CalendarEvents (ExchangePowerShell) | Microsoft Learn
Connect-ExchangeOnline
Remove-CalendarEvents -Identity youremailaddress -CancelOrganizedMeetings -QueryStartDate 11-30-2025 -QueryWindowInDays 90 -PreviewOnly -Verbose
This will preview the meetings that would be cancelled in your calendar for the specified date range. After you verify the meetings, just remove -PreviewOnly -Verbose.
Please try and let me know the result.
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