diff --git a/dev/flux/src/errorHandler.ts b/dev/flux/src/errorHandler.ts
index 2f554eae90..6ba399dff6 100644
--- a/dev/flux/src/errorHandler.ts
+++ b/dev/flux/src/errorHandler.ts
@@ -18,14 +18,16 @@ export async function streamToJson(stream: ReadableStream<Uint8Array>): Promise<
 
 export const errorHandler = async <T>(response: Response) => {
     if (!response.ok) {
-        throw new ProsopoApiError('API.BAD_REQUEST', { context: { error: `HTTP error! status: ${response.status}` } })
+        throw new ProsopoApiError('API.BAD_REQUEST', {
+            context: { error: `HTTP error! status: ${response.status}`, code: response.status },
+        })
     }
     if (response.body && !response.bodyUsed) {
         const data = await streamToJson(response.body)
 
         if (data.status === 'error') {
             throw new ProsopoApiError('API.BAD_REQUEST', {
-                context: { error: `HTTP error! status: ${data.data.message} ` },
+                context: { error: `HTTP error! status: ${data.data.message} `, code: response.status },
             })
         }
         return data as T
diff --git a/packages/datasets/src/captcha/util.ts b/packages/datasets/src/captcha/util.ts
index 17235567a1..d1a27f4182 100644
--- a/packages/datasets/src/captcha/util.ts
+++ b/packages/datasets/src/captcha/util.ts
@@ -11,13 +11,13 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-import { ProsopoApiError, ProsopoEnvError } from '@prosopo/common'
+import { ProsopoDatasetError, ProsopoEnvError } from '@prosopo/common'
 
 export async function downloadImage(url: string): Promise<Uint8Array> {
     try {
         const response = await fetch(url)
         if (!response.ok) {
-            throw new ProsopoApiError('API.BAD_REQUEST', {
+            throw new ProsopoDatasetError('API.BAD_REQUEST', {
                 context: { error: `Network response was not ok, status: ${response.status}`, url },
             })
         }
diff --git a/packages/procaptcha/src/modules/Manager.ts b/packages/procaptcha/src/modules/Manager.ts
index d4d1fea4c9..e682fc53ea 100644
--- a/packages/procaptcha/src/modules/Manager.ts
+++ b/packages/procaptcha/src/modules/Manager.ts
@@ -30,15 +30,14 @@ import {
 import { ApiPromise } from '@polkadot/api/promise/Api'
 import { ExtensionWeb2, ExtensionWeb3 } from '@prosopo/account'
 import { Keyring } from '@polkadot/keyring'
+import { ProsopoCaptchaContract, wrapQuery } from '@prosopo/contract'
 import {
-    ProsopoApiError,
     ProsopoContractError,
     ProsopoDatasetError,
     ProsopoEnvError,
     ProsopoError,
     trimProviderUrl,
 } from '@prosopo/common'
-import { ProsopoCaptchaContract, wrapQuery } from '@prosopo/contract'
 import { ProviderApi } from '@prosopo/api'
 import { RandomProvider } from '@prosopo/captcha-contract/types-returns'
 import { WsProvider } from '@polkadot/rpc-provider/ws'
@@ -231,7 +230,7 @@ export function Manager(
             const challenge = await captchaApi.getCaptchaChallenge()
 
             if (challenge.captchas.length <= 0) {
-                throw new ProsopoApiError('DEVELOPER.PROVIDER_NO_CAPTCHA')
+                throw new ProsopoDatasetError('DEVELOPER.PROVIDER_NO_CAPTCHA')
             }
 
             // setup timeout, taking the timeout from the individual captcha or the global default
@@ -452,7 +451,9 @@ export function Manager(
 
     const getCaptchaApi = () => {
         if (!state.captchaApi) {
-            throw new ProsopoApiError('API.UNKNOWN', { context: { error: 'Captcha api not set', state } })
+            throw new ProsopoEnvError('API.UNKNOWN', {
+                context: { error: 'Captcha api not set', state },
+            })
         }
         return state.captchaApi
     }
diff --git a/packages/provider/src/api/authMiddleware.ts b/packages/provider/src/api/authMiddleware.ts
index df55146c2d..34ef4ce56a 100644
--- a/packages/provider/src/api/authMiddleware.ts
+++ b/packages/provider/src/api/authMiddleware.ts
@@ -46,12 +46,14 @@ const extractHeaders = (req: Request) => {
 
     if (!signature || !blocknumber) {
         throw new ProsopoApiError('CONTRACT.INVALID_DATA_FORMAT', {
-            context: { error: 'Missing signature or block number' },
+            context: { error: 'Missing signature or block number', code: 400 },
         })
     }
 
     if (Array.isArray(signature) || Array.isArray(blocknumber) || !isHex(signature)) {
-        throw new ProsopoApiError('CONTRACT.INVALID_DATA_FORMAT', { context: { error: 'Invalid header format' } })
+        throw new ProsopoApiError('CONTRACT.INVALID_DATA_FORMAT', {
+            context: { error: 'Invalid header format', code: 400 },
+        })
     }
 
     return { signature, blocknumber }
@@ -75,6 +77,7 @@ const verifyBlockNumber = async (blockNumber: string, tasks: Tasks) => {
         throw new ProsopoApiError('API.BAD_REQUEST', {
             context: {
                 error: `Invalid block number ${parsedBlockNumber}, current block number is ${currentBlockNumber}`,
+                code: 400,
             },
         })
     }
@@ -84,6 +87,8 @@ const verifySignature = (signature: string, blockNumber: string, pair: KeyringPa
     const u8Sig = hexToU8a(signature)
 
     if (!pair.verify(blockNumber, u8Sig, pair.publicKey)) {
-        throw new ProsopoApiError('GENERAL.INVALID_SIGNATURE', { context: { error: 'Signature verification failed' } })
+        throw new ProsopoApiError('GENERAL.INVALID_SIGNATURE', {
+            context: { error: 'Signature verification failed', code: 401 },
+        })
     }
 }
diff --git a/provider-gui/services/api/api.ts b/provider-gui/services/api/api.ts
index 6b38495e49..b0032defdd 100644
--- a/provider-gui/services/api/api.ts
+++ b/provider-gui/services/api/api.ts
@@ -17,7 +17,7 @@ import { ProsopoApiError } from '@prosopo/common'
 async function handleResponse(response: Response) {
     if (!response.ok) {
         const errorMessage = await response.text()
-        throw new ProsopoApiError('API.BAD_REQUEST', { context: { error: errorMessage } })
+        throw new ProsopoApiError('API.BAD_REQUEST', { context: { error: errorMessage, code: 400 } })
     }
     return response.json()
 }