Errors

 
Hi expert,
I have an error as below. When clicking the page number without selecting any page size from the dropdown list, the program runs fine, but if I click the page number and then select the dropdown list, I have the error. How to fix it? Appreciate it!!!
Error: Invalid CurrentPageIndex value. It must be >= 0 and < the PageCount.
Line  569:  dgPopularFAQs.DataBind()
 
Below are the codes:

Protected Sub NumRowsSelected_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)
        If (NumRowsSelected.SelectedItem.Value = "ALL") Then
            dgPopularFAQs.AllowPaging = false
        Else
           dgPopularFAQs.AllowPaging = true
     &n ...