Two leds blink with one button

I attempted to use a switch case and it works halfway it turns on the green led after blink but after going again it doesn't turn on the red LED it just goes back to green.
switch (mes) { case 1: if (buttonState == HIGH){ buttonState = LOW; digitalWrite (ledPin2,HIGH); digitalWrite (ledPin,LOW); delay (100); break; } case 2: digitalWrite (ledPin,LOW); digitalWrite (ledPin2,HIGH);
I already attempted using the same thing as case 1 but changing the Pins for the red one and it doesn't work it goes back to the basic code.