Multiple Keyboard iOS

Hello guys, I'm trying to insert in my app more parameters like User Name, Email, Nickname ecc but with no success. I've used this code, am I missing something?

 var text1 : String;
 var text2 : String;
 var isTyping : boolean;
  
 function OnGUI() {
     if (GUI.Button(Rect(10, 10, 200, 32), text1) && !isTyping) {
         StartCoroutine(COInputText1());
     }
     if (GUI.Button(Rect(10, 50, 200, 32), text2) && !isTyping) {
         StartCoroutine(COInputText2());
     }
 }
  
 function COInputText1() {
     isTyping = true;
     var keyboard : iPhoneKeyboard;
     keyboard = iPhoneKeyboard.Open(text1);
     yield keyboard;
     text1 = keyboard.text;
     isTyping = false;
 }
  
 function COInputText2() {
     isTyping = true;
     var keyboard : iPhoneKeyboard;
     keyboard = iPhoneKeyboard.Open(text2);
     yield keyboard;
     text2 = keyboard.text;
     isTyping = false;
 }