diff --git a/src/client/stores/CalculationStore/Effects/reaction.ts b/src/client/stores/CalculationStore/Effects/reaction.ts
index 08a22bc..a4e556c 100644
--- a/src/client/stores/CalculationStore/Effects/reaction.ts
+++ b/src/client/stores/CalculationStore/Effects/reaction.ts
@@ -9,6 +9,10 @@ const reactionEffects: IReactionEffect[] = [
       return values.lead;
     },
     effect: async leadId => {
+      if (!leadId) {
+        calculationStore.setValue('opportunity', null);
+        return;
+      }
       const lead = calculationStore.options.selectLead?.find(
         x => x.leadid === leadId,
       );