Cannot change TextMeshPro text

I have a playing card prefab which contains a TextMeshPro object for displaying a number. I wish to instantiate the prefab and change the number. In some cases I can change the number, in other cases I cannot.

I started by creating a sample scene to experiment with the code for changing the text. This scene contains an object with a script for changing the text. In the Start method of the script I instantiate the prefab and change the number. This works fine. See the code below.

Code (CSharp):

1.         Vector3 position = new Vector3(0.0f, 0.0f, 0.0f);
2.         card = Instantiate(cardPrefab, position, Quaternion.Euler(0.0f, 180f, 0f));
3.         GameObject.Find("UpperLeftNumber").GetComponentInChildren<TextMeshPro>().text = "88";
4.  

When I move the code from the sample scene to my game scene, it does not work. In the game scene, the code is called in a ClientRPC.

I have tried many combinations of SetActive(true/false), SetText, ForceMeshUpdate, and SetAllDirty. Nothing works, the number doesn't change. If there is a trick to using one or more of these methods, then please help me. Perhaps I am using them in the wrong order?

There seems to be a distinct difference between instantiating in Start rather than in a ClientRPC. Can someone explain this difference?

 

Problem solved. There were two objects name UpperLeftNumber in my scene. Switching from

Code (CSharp):

1. GameObject.Find(...)

to

Code (CSharp):

1. card.GetComponentsInChildren()...

solved the problem.