diff --git a/src/tests/unit/api-next/get-matching-symbols.ts b/src/tests/unit/api-next/get-matching-symbols.test.ts
similarity index 100%
rename from src/tests/unit/api-next/get-matching-symbols.ts
rename to src/tests/unit/api-next/get-matching-symbols.test.ts
diff --git a/src/tests/unit/api-next/subscription-registry.test.ts b/src/tests/unit/api-next/subscription-registry.test.ts
new file mode 100644
index 00000000..29e380c7
--- /dev/null
+++ b/src/tests/unit/api-next/subscription-registry.test.ts
@@ -0,0 +1,72 @@
+import { Subscription } from "rxjs";
+import { IBApiNext, IBApiNextError } from "../../..";
+
+const _awaitTimeout = (delay: number): Promise<unknown> =>
+  new Promise((resolve): NodeJS.Timeout => setTimeout(resolve, delay * 1000));
+
+describe("Subscription registry Tests", () => {
+  jest.setTimeout(20000);
+
+  const clientId = Math.floor(Math.random() * 32766) + 1; // ensure unique client
+
+  let subscription$: Subscription;
+  let api: IBApiNext;
+  let error$: Subscription;
+
+  beforeEach(() => {
+    api = new IBApiNext();
+
+    if (!error$) {
+      error$ = api.errorSubject.subscribe((error) => {
+        if (error.reqId === -1) {
+          console.warn(`${error.error.message} (Error #${error.code})`);
+        } else {
+          console.error(
+            `${error.error.message} (Error #${error.code}) ${
+              error.advancedOrderReject ? error.advancedOrderReject : ""
+            }`,
+          );
+        }
+      });
+    }
+
+    try {
+      api.connect(clientId);
+    } catch (error) {
+      console.error(error.message);
+    }
+  });
+
+  afterEach(() => {
+    if (api) {
+      api.disconnect();
+      api = undefined;
+    }
+  });
+
+  it("Twice the same event callback bug", (done) => {
+    subscription$ = api.getOpenOrders().subscribe({
+      next: (data) => {
+        console.log(data);
+      },
+      error: (err: IBApiNextError) => {
+        console.error(`getOpenOrders failed with '${err.error.message}'`);
+      },
+    });
+
+    api
+      .getAllOpenOrders()
+      .then((orders) => {
+        console.log(orders);
+        done();
+      })
+      .catch((err: IBApiNextError) => {
+        console.error(`getAllOpenOrders failed with '${err}'`);
+      });
+
+    // awaitTimeout(15).then(() => {
+    //   subscription$.unsubscribe();
+    //   done();
+    // });
+  });
+});