diff --git a/src/index.test.ts b/src/index.test.ts
index 89c5be4..410288d 100644
--- a/src/index.test.ts
+++ b/src/index.test.ts
@@ -52,7 +52,7 @@ describe('index', () => {
         privateKey = priv;
         dataRequest = {
           healthDepartment: 'Test Health Department',
-          keyOfHealthDepartment: publicKey,
+          key: Buffer.from(publicKey, 'utf-8').toString('base64'),
           keyReferenz: 'random-string-keyref',
           start: '2011-10-05T14:48:00.000Z',
           end: '2021-10-05T14:48:00.000Z',
@@ -77,7 +77,7 @@ describe('index', () => {
     });
     expect(mockedAxios.get).toHaveBeenCalledWith('/data-requests/12345-abcde');
 
-    mockedAxios.post.mockResolvedValue({ status: 200, data: { success: true } });
+    mockedAxios.post.mockResolvedValue({ status: 201, data: { success: true } });
     await iris.sendContactsEvents('12345-abcde', submission, {
       firstName: 'Hans',
       lastName: 'Müller',
diff --git a/src/lib/Iris.ts b/src/lib/Iris.ts
index 3d8c519..3dadfbf 100644
--- a/src/lib/Iris.ts
+++ b/src/lib/Iris.ts
@@ -36,7 +36,7 @@ export default class Iris {
     }
     const dataRequest = response.data as IrisDataRequestDTO;
     this.codeKeyMap.set(code, {
-      keyOfHealthDepartment: dataRequest.keyOfHealthDepartment,
+      key: dataRequest.key,
       keyReferenz: dataRequest.keyReferenz,
     });
     return {
@@ -52,15 +52,17 @@ export default class Iris {
       throw new Error("Code could not be found in key map. Did you perform 'getDataRequest' before?");
     }
     const keys = this.codeKeyMap.get(code);
-    const { dataToTransport, keyToTransport, nonce } = encryptData(keys.keyOfHealthDepartment, data);
+    const { dataToTransport, keyToTransport, nonce } = encryptData(keys.key, data);
     const response = await this.axiosInstance.post(`/data-submissions/${code}/contacts_events`, {
-      checkCode: [ getNameCheckHash(user.firstName, user.lastName), getBirthDateCheckHash(user.birthDate) ].filter(c => !!c),
+      checkCode: [getNameCheckHash(user.firstName, user.lastName), getBirthDateCheckHash(user.birthDate)].filter(
+        (c) => !!c,
+      ),
       secret: keyToTransport,
       keyReferenz: keys.keyReferenz,
       encryptedData: dataToTransport,
-      nonce 
+      nonce,
     } as IrisContactsEventsSubmissionDTO);
-    if (response.status !== 200) {
+    if (response.status !== 201) {
       console.error('IRIS Gateway responded the following data', response.data);
       throw new Error(`Request failed with status Code ${response.status}`);
     }
diff --git a/src/lib/crypto.ts b/src/lib/crypto.ts
index d13c081..e030072 100644
--- a/src/lib/crypto.ts
+++ b/src/lib/crypto.ts
@@ -9,7 +9,7 @@ export function encryptData(
   const cipher = crypto.createCipheriv('AES-256-CBC', key, nonce);
   const dataString = JSON.stringify(data);
   const encryptedData = Buffer.concat([cipher.update(dataString, 'utf8'), cipher.final()]);
-  const encryptedKey = crypto.publicEncrypt({ key: keyOfHealthDepartment }, key);
+  const encryptedKey = crypto.publicEncrypt({ key: Buffer.from(keyOfHealthDepartment, 'base64') }, key);
   return {
     dataToTransport: encryptedData.toString('base64'),
     keyToTransport: encryptedKey.toString('base64'),
diff --git a/src/types/IrisCodeKeyMap.ts b/src/types/IrisCodeKeyMap.ts
index 0a130cd..70f08bc 100644
--- a/src/types/IrisCodeKeyMap.ts
+++ b/src/types/IrisCodeKeyMap.ts
@@ -1,5 +1,5 @@
 import IrisDataRequestDTO from './dto/IrisDataRequestDTO';
 import IrisCode from './IrisCode';
 
-type IrisCodeKeyMap = Map<IrisCode, Pick<IrisDataRequestDTO, 'keyOfHealthDepartment' | 'keyReferenz'>>;
+type IrisCodeKeyMap = Map<IrisCode, Pick<IrisDataRequestDTO, 'key' | 'keyReferenz'>>;
 export default IrisCodeKeyMap;
diff --git a/src/types/dto/IrisDataRequestDTO.ts b/src/types/dto/IrisDataRequestDTO.ts
index 1335608..1680e1c 100644
--- a/src/types/dto/IrisDataRequestDTO.ts
+++ b/src/types/dto/IrisDataRequestDTO.ts
@@ -1,6 +1,6 @@
 export default interface IrisDataRequestDTO {
     healthDepartment: string;
-    keyOfHealthDepartment: string;
+    key: string;
     keyReferenz: string;
     start?: string;
     end?: string;