# Common Error Code

<table><thead><tr><th width="250">Error Code</th><th>Solution</th></tr></thead><tbody><tr><td>400 - Bad Request</td><td>Please double check the parameters in the request</td></tr><tr><td>401, 402 - Unauthorized</td><td>Please use the correct API Key (Only for Pro User)</td></tr><tr><td>403 - Forbidden</td><td>Please contact us to whitelist your IP, seems you have broken some of the security strategies</td></tr><tr><td>404 - Not Found</td><td>Please double check whether the request URL exist.</td></tr><tr><td>429 - Too Many Requests</td><td>Please lower your request rate</td></tr><tr><td>500 - Internal Server Error</td><td>Please double check your request and contact us</td></tr><tr><td>502 - Bad Gateway</td><td>The proxy gateway server cannot receive the respond</td></tr><tr><td>503 - Service Unavailable</td><td>Server is overload or maintenance</td></tr><tr><td>504 - Gateway Timeout</td><td>Server timeout</td></tr><tr><td>509 - Concurrency Limit</td><td>Please lower the concurrency</td></tr></tbody></table>