nested For loop and handle error with try...catch in visual basic

Question

I try to run this code but the inner loop doesn't work

Sub Main()
        Dim intyrs As Integer
        Dim sngtotalRain, sngrain As Single
        Dim i, j, flag, flag1 As Integer
        flag = 1
        flag1 = 1
        sngtotalRain = 0

        Console.WriteLine("Enter the number of years to use for the average rainfall: ")
        While flag = 1
            Try
                intyrs = Console.ReadLine()
                Console.WriteLine("")
                For i = 1 To intyrs
                    Console.WriteLine("For year" & i)
                    While flag1 = 1
                        For j = 1 To 12

                            Console.WriteLine("Enter the rainfall amount for month " & j & " : ")
                            Try
                                sngrain = Console.ReadLine()

                            Catch

                                Console.WriteLine("Please enter amount of rainfall")

                            End Try
                            sngtotalRain += sngrain
                        Next
                        flag1 = 0
                    End While
                Next
                flag = 0
            Catch
                Console.WriteLine("Please enter numerical value") 'Showing the error for not inputting numeric values.
            End Try
        End While
        Console.WriteLine("")
        Console.WriteLine("For " & intyrs * 12 & " Total months, the average rainfall is " & sngtotalRain / intyrs / 12 & ", and the Total rainfall is " & sngtotalRain & " inches")
        Console.ReadKey()

    End Sub
End Module

When I enter a w, I want to go back month 2:

Enter the number of years to use for the average rainfall: 1

For year1 Enter the rainfall amount for month 1 : 1 Enter the rainfall amount for month 2 : w Please enter amount of rainfall Enter the rainfall amount for month 3 :