I'm trying to patch a new record to the OOB booking alert entity. There's an custom optionset that specify which type of booking alert (ie. notes, photo etc).
When I use this formula: Patch('Booking Alerts', Defaults('Booking Alerts'), {'Booking Alert Type': 'Booking Alert Type'.Note, Subject: Note_Subject_TextInput.Text})
it gave me this error.

I'm not sure how to resolve. Please help.