Unable to remove Internet Calendar with Delete - read only error

I didn’t realize Microsoft Ignite 2021 I had added an emclient internet calendar that perhaps now is no longer online.

I get an error trying to Delete the calendar “Deleting the folder failed due to the following error: Unable to remove the item, because the account is read only.”

OPS:
[Web Calendar]Synchronizing folder ‘Internet Calendars/Microsoft Ignite 2021 Calendar’ failed due to the following error: One of the identified items was in an invalid format.
LOG:

8:58:41 AM Internet Calendars Web Calendar Synchronizing folder ‘/Microsoft Ignite 2021 Calendar’
8:58:42 AM Internet Calendars [Web Calendar] MailClient.Storage.Application.OperationException: Synchronizing folder ‘Internet Calendars/Microsoft Ignite 2021 Calendar’ failed due to the following error: One of the identified items was in an invalid format.
—> System.FormatException: One of the identified items was in an invalid format.
at MailClient.VObject.CalendarReader.LoadCalendar(Calendar calendar)
at MailClient.VObject.Calendar…ctor(TextReader reader)
at MailClient.Protocols.WebCal.WebCalCalendarSynchronizer.Synchronize(IItemSynchronizeContext1 synchronizeContext, Folder folder, CancellationToken cancellationToken) at MailClient.Protocols.Common.ItemSynchronizer2.<>c__DisplayClass37_1.b__6(WorkerStatus status, CancellationToken ct)
at MailClient.Protocols.WebCal.WebCalGenericCommand.Execute(WorkerStatus status)
— End of inner exception stack trace —
GUIStatus_Exception_Reported = True