One of my variables keeps resetting.

Hi, I'm trying to get this code to remember what the last randomly generated number (rand) is by assigning it to lastRand. The idea is that something different happens if the RNG gives the same number twice or more in a row. However, the lastRand variable keeps resetting after break. Am I missing something really obvious here? 'cos it sure feels like it. Thanks in advance!

     void OnTriggerEnter (Collider ship)
     {
         Debug.Log("lastRand beginning = " + lastRand);
         rand = Random.Range(1, 3);
         
         
         switch (rand)
         {
             case 1:
                 {
                     // Next ring will be on the left
                     
                     left.GetComponent<Text>().enabled = true;
                     StartCoroutine(killTextLeft());
                     Debug.Log("line 41 Rand is: " + rand);
                     if (lastRand != 1)
                     {
                         newPosition = (thisPosition + new Vector3(-50, 0, 50));
                     }
                     else if (lastRand == 1)
                     {
                         Debug.Log("far left");
                         newPosition = (thisPosition + new Vector3(-100, 0, 50));
                     }
 
                     Instantiate(newRing, newPosition, Quaternion.Euler(0, -45, 0));
                     lastRand = rand;
                     Debug.Log("line 54 lastRand is: " + lastRand); // lastRand is still what it should be here
                     return;
                 }
 
             case 2:
                 {
                     //Next ring will be on the right
                     right.GetComponent<Text>().enabled = true;
                     StartCoroutine(killTextRight());
                     Debug.Log("line 63 lastRand is: " + rand);
                     if (lastRand != 2)
                     {
                         newPosition = (thisPosition + new Vector3(50, 0, 50));
                     }
                     else if (lastRand == 2)
                     {
                         newPosition = (thisPosition + new Vector3(100, 0, 50));
                     }
                     Instantiate(newRing, newPosition, Quaternion.Euler(0, 45, 0));
                     lastRand = rand;
                     Debug.Log("line 74 lastRand is: " + lastRand); // lastRand is still what it should be here
                     return;
                 }
 
         }
     }