diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/controllers/AccountController.java b/service/src/main/java/org/whispersystems/textsecuregcm/controllers/AccountController.java
index 67d822665..7daa6e560 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/controllers/AccountController.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/controllers/AccountController.java
@@ -143,6 +143,7 @@ public class AccountController {
   @PUT
   @Path("/apn/")
   @Consumes(MediaType.APPLICATION_JSON)
+  @Produces(MediaType.APPLICATION_JSON)
   @ChangesDeviceEnabledState
   public void setApnRegistrationId(@Auth DisabledPermittedAuthenticatedAccount disabledPermittedAuth,
       @NotNull @Valid ApnRegistrationId registrationId) {