PhotonView with ID2 has no (Non-static) method "UpdateHealthBar" marked with punRPC(C#) args int32

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Hey im currently having a problem with my HP header, I have a PhotonView on it and a PunRPC on my updateHealthBar.

Im not exactly sure what the problem could be, but at first i just thought that it couldnt find my Photonview on the headerInfo gameobject, but now i dont know anymore. So if anyone has any idea of how to fix it that would be great.