diff --git a/jestconfig.json b/jestconfig.json
index a780067..b5e6a9b 100644
--- a/jestconfig.json
+++ b/jestconfig.json
@@ -4,7 +4,7 @@
   },
   "testRegex": "(/__tests__/.*|(\\.|/)(test|spec))\\.(jsx?|tsx?)$",
   "moduleFileExtensions": ["ts", "tsx", "js", "jsx", "json", "node"],
-  "collectCoverage": false,
+  "collectCoverage": true,
   "coverageThreshold": {
     "global": {
       "branches": 50,
diff --git a/src/__tests__/TuitioAuthentication.test.ts b/src/__tests__/TuitioAuthentication.test.ts
index c885de0..6c4fcc1 100644
--- a/src/__tests__/TuitioAuthentication.test.ts
+++ b/src/__tests__/TuitioAuthentication.test.ts
@@ -30,3 +30,39 @@ test("Tuitio client authentication", async () => {
   const emptyStorage = fetch();
   expect(emptyStorage.userName).toBeNull();
 });
+
+test("Tuitio client failed authentication", async () => {
+  (axios.request as jest.Mock).mockRejectedValueOnce({
+    response: {
+      status: 500,
+      data: { title: "Internal server error" }
+    }
+  });
+
+  const client = new TuitioClient("https://test.com/api");
+
+  try {
+    await client.authenticate("user", "pass");
+  } catch (error: any) {
+    expect(error.title).toBe("Internal server error");
+    expect(error.message).toBe("Internal server error");
+  }
+});
+
+test("Tuitio client failed authentication with unhandled exception", async () => {
+  (axios.request as jest.Mock).mockRejectedValueOnce({
+    response: {
+      status: 500,
+      error: { message: "Internal server error" }
+    }
+  });
+
+  const client = new TuitioClient("https://test.com/api");
+
+  try {
+    await client.authenticate("user", "pass");
+  } catch (error: any) {
+    expect(error.response.status).toBe(500);
+    expect(error.response.error.message).toBe("Internal server error");
+  }
+});
diff --git a/src/client.ts b/src/client.ts
index c883a97..6fdc5b0 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -11,12 +11,11 @@ async function request(url: string, method: string) {
     return res.data;
   } catch (error: any) {
     if (error.response && error.response.data) {
-      throw (
-        {
-          ...error.response.data,
-          message: error.response.data.detail || error.response.data.title
-        } || error
-      );
+      const { detail, title } = error.response.data;
+      throw {
+        ...error.response.data,
+        message: detail || title
+      };
     }
     throw error;
   }