diff --git a/src/repositories/shuttle/RedisShuttleRepository.ts b/src/repositories/shuttle/RedisShuttleRepository.ts
index 8d20e9c..a18ca58 100644
--- a/src/repositories/shuttle/RedisShuttleRepository.ts
+++ b/src/repositories/shuttle/RedisShuttleRepository.ts
@@ -486,7 +486,7 @@ export class RedisShuttleRepository extends EventEmitter implements ShuttleGette
         await this.addTravelTimeDataPoint({ routeId, fromStopId, toStopId, }, travelTimeSeconds, travelTimeTimestamp);
       }
 
-      await this.updateShuttleLastStopArrival(shuttle, {
+      await this.updateShuttleLastStopArrival(shuttle.id, {
         stopId: arrivedStop.id,
         timestamp: new Date(travelTimeTimestamp),
       })
@@ -626,8 +626,8 @@ export class RedisShuttleRepository extends EventEmitter implements ShuttleGette
     };
   }
 
-  public async updateShuttleLastStopArrival(shuttle: IShuttle, lastStopArrival: ShuttleStopArrival) {
-    const key = this.createShuttleLastStopKey(shuttle.id);
+  public async updateShuttleLastStopArrival(shuttleId: string, lastStopArrival: ShuttleStopArrival) {
+    const key = this.createShuttleLastStopKey(shuttleId);
     await this.redisClient.hSet(key, {
       stopId: lastStopArrival.stopId,
       timestamp: lastStopArrival.timestamp.toISOString(),
diff --git a/src/repositories/shuttle/__tests__/RedisShuttleRepository.test.ts b/src/repositories/shuttle/__tests__/RedisShuttleRepository.test.ts
index b99a5cb..9cb2220 100644
--- a/src/repositories/shuttle/__tests__/RedisShuttleRepository.test.ts
+++ b/src/repositories/shuttle/__tests__/RedisShuttleRepository.test.ts
@@ -212,7 +212,7 @@ describe("RedisShuttleRepository", () => {
         timestamp: new Date("2024-01-15T10:30:00Z"),
       };
 
-      await repository.updateShuttleLastStopArrival(shuttle, stopArrival);
+      await repository.updateShuttleLastStopArrival(shuttle.id, stopArrival);
       const result = await repository.getShuttleLastStopArrival(shuttle.id);
 
       expect(result).toBeDefined();
@@ -243,8 +243,8 @@ describe("RedisShuttleRepository", () => {
         timestamp: new Date("2024-01-15T10:35:00Z"),
       };
 
-      await repository.updateShuttleLastStopArrival(shuttle, firstArrival);
-      await repository.updateShuttleLastStopArrival(shuttle, secondArrival);
+      await repository.updateShuttleLastStopArrival(shuttle.id, firstArrival);
+      await repository.updateShuttleLastStopArrival(shuttle.id, secondArrival);
 
       const result = await repository.getShuttleLastStopArrival(shuttle.id);