diff --git a/src/main/scala/elevate/heuristic_search/heuristics/MCTS.scala b/src/main/scala/elevate/heuristic_search/heuristics/MCTS.scala
index 93f04200..40203a5c 100644
--- a/src/main/scala/elevate/heuristic_search/heuristics/MCTS.scala
+++ b/src/main/scala/elevate/heuristic_search/heuristics/MCTS.scala
@@ -103,7 +103,7 @@ class MCTS[P] extends Heuristic[P] {
           rollout = choose_valid_solution_randomly(panel = panel, actions = actions, rollout._2)
 
           // check if rollout is empty
-          if (rollout == null) {
+          if (rollout._1 == null) {
             isTerminal = true
           } else {
             rollout._1.solutionSteps.foreach(step => println(s"""[${step.strategy}, ${step.location}]"""))