diff --git a/src/infrastructure/repository/RequestRepositoryFile.test.ts b/src/infrastructure/repository/RequestRepositoryFile.test.ts
index 23de7aa..4964611 100644
--- a/src/infrastructure/repository/RequestRepositoryFile.test.ts
+++ b/src/infrastructure/repository/RequestRepositoryFile.test.ts
@@ -177,6 +177,38 @@ describe('persistResponseForRequest', () => {
     });
     expect(bodyContent).toEqual('Hello world');
   });
+
+  it('should persist no content-type as txt with their meta data', async () => {
+    // Given
+    const requestRepository = getRequestRepository();
+    const inputRequest = new Request('GET', '/text', {}, '');
+    const inputResponse = new Response(200, {}, 'Hello world');
+
+    // When
+    await requestRepository.persistResponseForRequest(
+      inputRequest,
+      inputResponse
+    );
+
+    const metadataContent = await fs.readJSON(
+      `${OUTPUT_DIRECTORY}/get__text-${inputRequest.id}/metadata.json`
+    );
+    const bodyContent = await fs.readFile(
+      `${OUTPUT_DIRECTORY}/get__text-${inputRequest.id}/body.txt`,
+      'utf-8'
+    );
+
+    //Then
+    expect(metadataContent).toEqual({
+      method: 'GET',
+      status: 200,
+      url: '/text',
+      requestBody: '',
+      requestHeaders: {},
+      responseHeaders: {},
+    });
+    expect(bodyContent).toEqual('Hello world');
+  });
 });
 
 describe('getResponseByRequestId', () => {
@@ -228,6 +260,19 @@ describe('getResponseByRequestId', () => {
       )
     );
   });
+
+  it('should return null when the request does not exist', async () => {
+    // Given
+    const requestId = 'does-not-exist';
+
+    // When
+    const response = await requestRepositorysitory.getResponseByRequestId(
+      requestId
+    );
+
+    //Then
+    expect(response).toBeNull();
+  });
 });
 
 describe('getAllRequests', () => {
diff --git a/src/infrastructure/repository/RequestRepositoryFile.ts b/src/infrastructure/repository/RequestRepositoryFile.ts
index b63d91d..a9b507e 100644
--- a/src/infrastructure/repository/RequestRepositoryFile.ts
+++ b/src/infrastructure/repository/RequestRepositoryFile.ts
@@ -19,6 +19,7 @@ function isXml(contentType: string | undefined) {
   if (!contentType) {
     return false;
   }
+
   const lowerCaseContentType = contentType.toLowerCase();
 
   return (
diff --git a/src/infrastructure/repository/RequestRepositoryMemory.ts b/src/infrastructure/repository/RequestRepositoryMemory.ts
index 3db1a26..340beb1 100644
--- a/src/infrastructure/repository/RequestRepositoryMemory.ts
+++ b/src/infrastructure/repository/RequestRepositoryMemory.ts
@@ -1,3 +1,5 @@
+/* istanbul ignore file */
+
 import { RequestRepository } from '../../domain/repository';
 import { Request, Response } from '../../domain/entity';
 
diff --git a/src/infrastructure/service/NetworkServiceAxios.test.ts b/src/infrastructure/service/NetworkServiceAxios.test.ts
index 10ae3ae..6e4abec 100644
--- a/src/infrastructure/service/NetworkServiceAxios.test.ts
+++ b/src/infrastructure/service/NetworkServiceAxios.test.ts
@@ -194,3 +194,32 @@ describe('Headers handling', () => {
     });
   });
 });
+
+describe('error handling', () => {
+  it('should throw an error when the error does not have a response', async () => {
+    expect.assertions(1);
+    // Given
+    ((axios as any) as jest.Mock).mockRejectedValue(
+      new Error('Failed to fetch')
+    );
+    const request = new Request(
+      'GET',
+      '/test',
+      {
+        authorization: 'bearer token',
+      },
+      ''
+    );
+    const networkService = new NetworkServiceAxios({
+      targetUrl: 'http://localhost',
+    });
+
+    // When
+    try {
+      await networkService.executeRequest(request);
+    } catch (err) {
+      // Then
+      expect(err).toBeDefined();
+    }
+  });
+});