diff --git a/packages/database/e2e/query/on.e2e.js b/packages/database/e2e/query/on.e2e.js
index 3643c1b09a..9f46daf73f 100644
--- a/packages/database/e2e/query/on.e2e.js
+++ b/packages/database/e2e/query/on.e2e.js
@@ -108,7 +108,7 @@ describe('database().ref().on()', function () {
   });
 
   // the cancelCallback is never called for ref.on but ref.once works?
-  xit('should cancel when something goes wrong', async function () {
+  it('should cancel when something goes wrong', async function () {
     const successCallback = sinon.spy();
     const cancelCallback = sinon.spy();
     const ref = firebase.database().ref('nope');
diff --git a/packages/database/lib/DatabaseSyncTree.js b/packages/database/lib/DatabaseSyncTree.js
index 25f4e522db..29c3057804 100644
--- a/packages/database/lib/DatabaseSyncTree.js
+++ b/packages/database/lib/DatabaseSyncTree.js
@@ -263,7 +263,7 @@ class DatabaseSyncTree {
 
     if (once) {
       const subscription = SharedEventEmitter.addListener(eventRegistrationKey, event => {
-        this._onOnceRemoveRegistration(eventRegistrationKey, listener, event);
+        this._onOnceRemoveRegistration(eventRegistrationKey, listener)(event);
         subscription.remove();
       });
     } else {