Hope you are doing well ,
I have to replicated your issue at my end and i was able to get number Of Occurrences after Setting Range type as "numbered" .
Use the type property to specify the different types of recurrence Range to get the no of occurrence's.
Refer this Article for More details -https://learn.microsoft.com/en-us/graph/api/resources/recurrencerange?view=graph-rest-1.0
Hope this helps.
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