diff --git a/web/shared-worker/types/sqlite-query-executor.js b/web/shared-worker/types/sqlite-query-executor.js
--- a/web/shared-worker/types/sqlite-query-executor.js
+++ b/web/shared-worker/types/sqlite-query-executor.js
@@ -203,7 +203,7 @@
   markOutboundP2PMessageAsSent(messageID: string, deviceID: string): void;
   resetOutboundP2PMessagesForDevice(
     deviceID: string,
-    newDeviceID?: ?string,
+    newDeviceID: ?string,
   ): $ReadOnlyArray<string>;
 
   addInboundP2PMessage(message: InboundP2PMessage): void;
diff --git a/web/shared-worker/worker/shared-worker.js b/web/shared-worker/worker/shared-worker.js
--- a/web/shared-worker/worker/shared-worker.js
+++ b/web/shared-worker/worker/shared-worker.js
@@ -600,6 +600,7 @@
       sqliteQueryExecutor.beginTransaction();
       messageIDs = sqliteQueryExecutor.resetOutboundP2PMessagesForDevice(
         message.deviceID,
+        message.newDeviceID,
       );
       sqliteQueryExecutor.commitTransaction();
     } catch (e) {
diff --git a/web/types/worker-types.js b/web/types/worker-types.js
--- a/web/types/worker-types.js
+++ b/web/types/worker-types.js
@@ -236,7 +236,7 @@
 export type ResetOutboundP2PMessagesRequestMessage = {
   +type: 24,
   +deviceID: string,
-  +newDeviceID?: ?string,
+  +newDeviceID: ?string,
 };
 
 export type FetchMessagesRequestMessage = {