Unable to get Events from specific Calendar

I'm trying to get events from a Specific Calendar through MSGraph-SDK (dotnet) - Getting the events for my 'default' calendar is not a problem:

var calendar = await graphClient.Me.Calendar.CalendarView.Request(options).GetAsync();
if (calendar?.Count > 0)
    {
        foreach (Event current in calendar)
       etc. //All good here

But when trying to get events from a specific calendar gives me an error (no details about the error provided)

var calOne = await graphClient.Me.Calendars[cal1].CalendarView.Request().GetAsync(); // <=Error

(Please note that cal1 is a string with a correct calendar Id) Chances are I'm missing something, just don't know what. Thanks in advance.