How to Employ CJK’s AppleScript “makeASDate” Handler Without Error

I am attempting to employ the makeASDate handler shared by user CJK (which I lifted from his answer at Apple Script: Can’t get date of "2018-12-12 10:00 AM") in order to set up some calendar events, one per day, from a Numbers worksheet containing Date, Reading, and Page Numbers.

Here is my code, thus far:

set CalendarDates to {}
set CalendarDateMonths to {}
set CalendarDateDatesOfMonths to {}
set Passages to {}
set PageNumbers to {}
set theYear to 2021

tell application "Numbers" to tell the front document to tell the active sheet to tell table 1
    repeat with i from 2 to the count of cells of column "A" -- row 1 is a header
        set theCalendarDate to formatted value of cell i of column "A"
        set theCalendarDateMonth to the first word of theCalendarDate
        set theCalendarDateDateOfMonth to the second word of theCalendarDate
        set thePassage to formatted value of cell i of column "B"
        set thePageNumbers to formatted value of cell i of column "C"
        
        set the end of CalendarDates to theCalendarDate
        set the end of CalendarDateMonths to theCalendarDateMonth
        set the end of CalendarDateDatesOfMonths to theCalendarDateDateOfMonth
        set the end of Passages to thePassage
        set the end of PageNumbers to thePageNumbers
    end repeat
    
    set theCalendarDate to missing value
    set theCalendarDateMonth to missing value
    set theCalendarDateDateOfMonth to missing value
    set thePassage to missing value
    set thePageNumbers to missing value
end tell

repeat with i from 1 to the count of CalendarDates
    set theSummary to (item i of Passages)
    set theStartDate to makeASDate given |year|:theYear, |month|:(item i of CalendarDateMonths), |day|:(item i of CalendarDateDatesOfMonths), |hours|:7, |minutes|:30
    set theEndDate to makeASDate given |year|:theYear, |month|:(item i of CalendarDateMonths), |day|:(item i of CalendarDateDatesOfMonths), |hours|:8, |minutes|:30
    set theDescription to "Pages " & (item i of PageNumbers) & "of Tyndale's The Chronological Life Application Study Bible."
    set theURL to "https://www.biblegateway.com/passage/?search=" & urlEncode(item i of Passages) & "&version=AMP&interface=print"
    set theAlldayEvent to false
    set theStampDate to current date
    set theStatus to "none"
    set theLocation to "facetime:chrishota@gmail.com"
    
    tell application "Calendar"
        activate
        -- If calendar doesn't exist, create such. Note, this creates local. I don't yet know how to create an iCloud-based Calendar, yet iCloud calendars may be selected if pre-created.
        set theCalendarName to "Bible Readings"
        try
            set theCalendar to (first calendar where its name = theCalendarName)
        on error
            set theCalendarDescription to "Readings for the reading of the Bible, chronologically, in the span of one year."
            set theCalendar to make new calendar with properties {name:theCalendarName, description:theCalendarDescription}
        end try
        -- Ensure work is with the proper calendar.
        set theCalendar to (first calendar where its name = theCalendarName)
        
        tell calendar theCalendar
            make new event with properties {description:theDescription, start date:theStartDate, end date:theEndDate, theAlldayEvent:false, stamp date:current date, status:none, summary:theSummary, location:theLocation, url:"http://biblegateway.com/"}
        end tell
    end tell
end repeat

The Numbers worksheet is loading alright, yet on constructing the date with MakeASDate, I receive the error "The year parameter is missing for makeASDate."

Any assistance in correcting what's wrong would be helpful!

Edit: I have updated the code to:

    set theStartDate to makeASDate given year:2021, month:(item i of CalendarDateMonths as integer), day:(item i of CalendarDateDatesOfMonths as integer), hours:7, minutes:30, seconds:0
    set theEndDate to makeASDate given year:2021, month:(item i of CalendarDateMonths as integer), day:(item i of CalendarDateDatesOfMonths as integer), hours:8, minutes:30, seconds:0
    display dialog "CalendarDateMonths[" & i & "]" & ": " & (item i of CalendarDateMonths as integer) & linefeed & linefeed & "theStartDate: " & theStartDate & linefeed & linefeed & "theEndDate: " & theEndDate

Now when I compile and run the code, it returns March instead of February when I enter a value of "2" (I changed the format of the Date column in numbers to be m/d):