Invalid use of property

Using: Dim rs As dao.Recordset
there is a compile error in the following code:

   'v-- complile error: Invalid use of property ********
    rs = CurrentDb.OpenRecordset("SELECT tIssue.IssueID, tPeople.FirstName,

with "rs" selected.
-------
It goes away with Dim rs 'As dao.Recordset

But at line:

If rs.RecordCount > 0 Then <-- I get runtime error 438: Object doesn't support this property or method. The entire line "If rs.RecordCount > 0 Then" high-lighted yellow.

Question: Is this about some missing reference I need to add?

Thank you.
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Function fnName(IssueID As Long, FirstName As String, LastName As String) As String

    Dim rs As dao.Recordset
    Dim c As String
         
    'v-- complile error: Invalid use of property ********
    rs = CurrentDb.OpenRecordset("SELECT tIssue.IssueID, tPeople.FirstName, tPeople.LastName FROM tRequest INNER JOIN (tPeople INNER JOIN " & _
            "(tIssue INNER JOIN tSponser ON tIssue.IssueID = tSponser.Issue_ID) ON tPeople.PeopleID = " & _
            "tSponser.People_ID) ON tRequest.RequestID = tIssue.Request_ID =" & IssueID)
   
    If rs.RecordCount > 0 Then
        rs.MoveFirst
        Do Until rs.EOF
            strTemp = rs!FirstName & ", " & rs!LastName + ", "
        Loop
   
    End If
   
    strTemp = Left(strTemp, Len(strTemp) - 2)
   
    rs.Close
   
    fnName = strTemp
   
End Function