C# :: How To Show MessageBox In 2 Radio Button

I'm trying to do this :

when user chick first radio button a message1 will show with OK button
when user chick second radio button an another message2 will show with OK button

But its didn't work like this. its work like:

1- user chick first radio button
2- message1 will show with OK button
3- user click OK
4- user chick second radio button
5- message1 will show again with OK button
6- user click OK
7- then message2 will show again with OK button

so when user click in second time its show the 2 message the message1 then the message2

this is my code

private void radioButton2_CheckedChanged(object sender, EventArgs e) {
MessageBox.Show("Amount is ...
" + money, "Amount" , MessageBoxButtons.OK , MessageBoxIcon.Information);
}
private void radioButton1_CheckedChanged(object sender, EventArgs e) {
MessageBox.Show("Item name : " + arr[0].name ,
"Availability", MessageBoxButtons.OK, MessageBoxIcon.Information);
}