diff --git a/express-api/src/services/ches/chesServices.ts b/express-api/src/services/ches/chesServices.ts
index 5f564dc0d..1ab194f99 100644
--- a/express-api/src/services/ches/chesServices.ts
+++ b/express-api/src/services/ches/chesServices.ts
@@ -97,11 +97,19 @@ const sendAsync = async (endpoint: string, method: string, data: Record<string,
     body: data ? JSON.stringify(data) : undefined,
   });
 
+  if (!response.ok) {
+    logger.error({
+      message: 'CHES Error',
+      chesResponse: JSON.parse(await response.text()),
+    });
+    return null;
+  }
+
   const text = await response.text();
   if (text.length) {
     return JSON.parse(text);
   } else {
-    return {};
+    return null;
   }
 };
 
diff --git a/express-api/src/utilities/winstonLogger.ts b/express-api/src/utilities/winstonLogger.ts
index b4b22940e..62d3d95f3 100644
--- a/express-api/src/utilities/winstonLogger.ts
+++ b/express-api/src/utilities/winstonLogger.ts
@@ -1,8 +1,9 @@
 import { format, createLogger, transports } from 'winston';
 import constants from '@/constants';
 
-const { timestamp, combine, json } = format;
+const { timestamp, combine, json, prettyPrint } = format;
 const { TESTING } = constants;
+const { CONTAINERIZED } = process.env;
 
 /**
  * Creates a logger object that can be called to generate log messages.
@@ -19,7 +20,8 @@ const logger = createLogger({
     timestamp({
       format: 'YYYY-MM-DD hh:mm:ss.SSS A',
     }),
-    json(),
+    CONTAINERIZED ? json() : prettyPrint(),
+    format.errors({ stack: true }),
   ),
   transports: [new transports.Console()],
   silent: TESTING,
diff --git a/express-api/tests/unit/services/ches/chesServices.test.ts b/express-api/tests/unit/services/ches/chesServices.test.ts
index 85d2345e9..5faf0c5cc 100644
--- a/express-api/tests/unit/services/ches/chesServices.test.ts
+++ b/express-api/tests/unit/services/ches/chesServices.test.ts
@@ -23,6 +23,7 @@ describe('UNIT - Ches Services', () => {
         text: () => '{"access_token":"eyAiYSI6IDEgfQ==.ewoiZXhwIjoxCn0="}',
       }));
       _fetch.mockImplementationOnce(() => ({
+        ok: true,
         text: () => `{ "messages": [{}], "txId": "${randomUUID()}" }`,
       }));
       const response = await chesServices.sendEmailAsync(email, keycloak);
@@ -35,10 +36,37 @@ describe('UNIT - Ches Services', () => {
         text: () => '{"access_token":"eyAiYSI6IDEgfQ==.ewoiZXhwIjoxCn0="}',
       }));
       _fetch.mockImplementationOnce(() => ({
+        ok: false,
         text: () => `{ "messages": [{}], "txId": "${randomUUID()}" }`,
       }));
       expect(async () => await chesServices.sendEmailAsync(email, keycloak)).rejects.toThrow();
     });
+    it('should return null if the CHES response is not OK', async () => {
+      const email = produceEmail({ cc: ['john@doe.com'], bcc: ['john@doe.com'] });
+      const keycloak = producePimsRequestUser();
+      _fetch.mockImplementationOnce(() => ({
+        text: () => '{"access_token":"eyAiYSI6IDEgfQ==.ewoiZXhwIjoxCn0="}',
+      }));
+      _fetch.mockImplementationOnce(() => ({
+        ok: false,
+        text: () => `{ "messages": [{}], "txId": "${randomUUID()}" }`,
+      }));
+      const result = await chesServices.sendEmailAsync(email, keycloak);
+      expect(result).toBeNull();
+    });
+    it('should return null if the CHES response has no text length', async () => {
+      const email = produceEmail({ cc: ['john@doe.com'], bcc: ['john@doe.com'] });
+      const keycloak = producePimsRequestUser();
+      _fetch.mockImplementationOnce(() => ({
+        text: () => '{"access_token":"eyAiYSI6IDEgfQ==.ewoiZXhwIjoxCn0="}',
+      }));
+      _fetch.mockImplementationOnce(() => ({
+        ok: true,
+        text: () => ``,
+      }));
+      const result = await chesServices.sendEmailAsync(email, keycloak);
+      expect(result).toBeNull();
+    });
     it('should send email with extra config', async () => {
       const email: IEmail = produceEmail({});
       const keycloak = producePimsRequestUser();
@@ -55,6 +83,7 @@ describe('UNIT - Ches Services', () => {
         text: () => '{"access_token":"eyAiYSI6IDEgfQ==.ewoiZXhwIjoxCn0="}',
       }));
       _fetch.mockImplementationOnce(() => ({
+        ok: true,
         text: () => `{ "messages": [{}], "txId": "${randomUUID()}" }`,
       }));
       const response = await chesServices.sendEmailAsync(email, keycloak);
@@ -67,8 +96,8 @@ describe('UNIT - Ches Services', () => {
         text: () => '{"access_token":"eyAiYSI6IDEgfQ==.ewoiZXhwIjoxCn0="}',
       }));
       _fetch.mockImplementationOnce(() => ({
+        ok: true,
         text: () => `
-
           {
           
               "createdTS": 1560000000,
@@ -102,6 +131,7 @@ describe('UNIT - Ches Services', () => {
         text: () => '{"access_token":"eyAiYSI6IDEgfQ==.ewoiZXhwIjoxCn0="}',
       }));
       _fetch.mockImplementationOnce(() => ({
+        ok: true,
         text: () => `
             [
               {
@@ -143,6 +173,7 @@ describe('UNIT - Ches Services', () => {
         text: () => '{"access_token":"eyAiYSI6IDEgfQ==.ewoiZXhwIjoxCn0="}',
       }));
       _fetch.mockImplementationOnce(() => ({
+        ok: true,
         text: () => `
 
           {
@@ -177,6 +208,7 @@ describe('UNIT - Ches Services', () => {
         text: () => '{"access_token":"eyAiYSI6IDEgfQ==.ewoiZXhwIjoxCn0="}',
       }));
       _fetch.mockImplementationOnce(() => ({
+        ok: true,
         text: () => `
 
           {
@@ -202,6 +234,7 @@ describe('UNIT - Ches Services', () => {
         text: () => '{"access_token":"eyAiYSI6IDEgfQ==.ewoiZXhwIjoxCn0="}',
       }));
       _fetch.mockImplementationOnce(() => ({
+        ok: true,
         text: () => `
 
           {
@@ -238,6 +271,7 @@ describe('UNIT - Ches Services', () => {
         text: () => '{"access_token":"eyAiYSI6IDEgfQ==.ewoiZXhwIjoxCn0="}',
       }));
       _fetch.mockImplementationOnce(() => ({
+        ok: true,
         text: () => `
             [
               {