PhotonView with ID has no method marked with the [PunRPC](C#) property! BUT IT HAS ???

In my game 2 players only join a room and i have to switch turns between them so i do something like that:

 using UnityEngine;
 
 // .. more code
 public PhotonView photonView; // i get it from editor
 bool myTurn = false;
 
 void Start() {
     // .. some other code
 
     if (PhotonNetwork.player.isMasterClient) {
          myTurn = true;
     }
 }
 
 void Update() {
     // ... LOTS OF CODE
     if(myTurn) {
         // Play till i finish
     }
 
     if(EndOfTurn) {
         // ... Do things
 
         myTurn = false;
         photonView.RPC("SwitchTurns()", PhotonTargets.Others);
     }
 }
 
 // ... Many lines of code
 
 [PunRPC]
 void SwitchTurns()
 {
     myTurn = true;
 }

and my GameObject has the script and the PhotonView component (Owner is Fixed) with no Observed Components and I've tried observing the script same error too.

as you can see I'm not " using Photon; " nor " Photon.MonoBehaviour " if that have to do something...?

Please any clue would be great, Thank you!