Please manage the error 'Can not instantiate objects with a parent which is persistent.'

While there are several scenes, if you invoke prefab in this way an error will occur, but it works correctly on the game view. Is there a way to erase the error? Or, can you erase the error programatically? The version you are using is 2018.3.6f.

public void onenga ()
In case
objer = Instantiate (objj, objj.transform, true);
objer.transform.SetParent (transform);
objer.transform.GetChild (1). GetComponent  (). onClick.AddListener (onenga 2);

Thank you for thinking. This sentence is a translation