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Error codes

This reference lists all error codes returned by the Flireo API with explanations and recommended actions.

HTTP Status Codes#

Success Codes#

CodeNameDescription
200OKRequest succeeded
201CreatedResource created successfully
204No ContentRequest succeeded, no content returned (delete operations)

Client Error Codes#

CodeNameDescription
400Bad RequestInvalid request format or validation error
401UnauthorizedMissing or invalid API key
402Payment RequiredInsufficient credits balance
403ForbiddenValid API key but no access to this resource
404Not FoundResource doesn't exist
409ConflictResource already exists (duplicate)
422Unprocessable EntityRequest understood but cannot be processed
429Too Many RequestsRate limit exceeded

Server Error Codes#

CodeNameDescription
500Internal Server ErrorUnexpected server error
502Bad GatewayUpstream service unavailable
503Service UnavailableServer temporarily unavailable
504Gateway TimeoutUpstream service timeout

Error Response Format#

All errors follow this format:
{
  "error": {
    "code": "error_code",
    "message": "Human readable message",
    "param": "field_name",
    "type": "error_type"
  }
}
FieldDescription
codeMachine-readable error code
messageHuman-readable description
paramThe field that caused the error (if applicable)
typeError category

Error Codes by Category#

Authentication Errors#

CodeMessageSolution
unauthorizedInvalid or missing API keyCheck your API key is correct and included in the Authorization header
api_key_expiredAPI key has expiredGenerate a new API key in the dashboard
api_key_revokedAPI key has been revokedGenerate a new API key

Validation Errors#

CodeMessageSolution
invalid_requestRequest body is invalidCheck JSON syntax and required fields
missing_fieldMissing required fieldInclude all required fields
invalid_fieldField value is invalidCheck field format (e.g., E.164 for phone numbers)
invalid_phone_numberPhone number format invalidUse E.164 format: +31612345678
invalid_uuidInvalid UUID formatProvide a valid UUID
invalid_urlInvalid URL formatProvide a valid HTTPS URL

Resource Errors#

CodeMessageSolution
not_foundResource not foundVerify the resource ID exists
already_existsResource already existsThe phone number or resource is already registered
conflictResource conflictAnother resource is using this identifier

Billing Errors#

CodeMessageSolution
insufficient_creditsInsufficient credits balanceAdd credits in the billing dashboard
payment_requiredPayment requiredAdd credits to make outbound calls

Rate Limit Errors#

CodeMessageSolution
rate_limit_exceededToo many requestsWait and retry with exponential backoff
call_control_limitToo many call control commandsLimit to 10 commands per minute per call

Provider Errors#

CodeMessageSolution
provider_errorExternal provider errorCheck BYOK configuration and provider status
provider_timeoutProvider request timeoutRetry the request
invalid_api_keyBYOK API key invalidUpdate the API key via BYOK endpoint

Call Errors#

CodeMessageSolution
call_not_foundCall not foundVerify the call ID
call_not_activeCall is not in-progressCall control only works on active calls
invalid_destinationInvalid destination numberCheck phone number format

Handling Errors#

Example Error Handler (JavaScript)#

Retry Strategy#

For transient errors (429, 502, 503, 504), implement exponential backoff:

Related#

Authentication
Troubleshooting
Rate Limits
Modified at 2026-01-30 12:26:16
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