diff --git a/app/worker.ts b/app/worker.ts
index 179afae..3207336 100644
--- a/app/worker.ts
+++ b/app/worker.ts
@@ -146,9 +146,9 @@ export default function start(self: ServiceWorkerGlobalScope) {
 
     const stupid =
       existingSubscriptionId === undefined
-        ? postSubscription(newSubscription, db)
+        ? postSubscription(newSubscription.toJSON(), db)
         : putSubscription(
-            newSubscription,
+            newSubscription.toJSON(),
             existingSubscriptionId.subscriptionId
           )
     await stupid
@@ -157,7 +157,7 @@ export default function start(self: ServiceWorkerGlobalScope) {
   }
 
   async function postSubscription(
-    subscription: PushSubscription,
+    subscription: PushSubscriptionJSON,
     db: ReturnType<typeof database>
   ) {
     await sendMessage({
@@ -191,7 +191,7 @@ export default function start(self: ServiceWorkerGlobalScope) {
     }
   }
 
-  function putSubscription(subscription: PushSubscription, id: number) {
+  function putSubscription(subscription: PushSubscriptionJSON, id: number) {
     return fetch(`${process.env.BASE_URL}/api/subscription/${id}`, {
       method: "PUT",
       body: JSON.stringify(subscription),