---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/80701#article
headline: "80701: Parameter Validation Failed"
url: https://www.twilio.com/docs/api/errors/80701
inLanguage: en
dateModified: 2026-06-08T12:04:59.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 80701: Parameter Validation Failed

Log Level: WARNING

## Description

Twilio returns this warning when a request to a Proxy resource includes a parameter that does not match the expected schema, format, or allowed value for that endpoint. The warning can appear as `<parameter name>` is invalid. `<parameter is invalid>`.

### Possible causes

* A required parameter for the resource you are creating was omitted or sent under the wrong field. For example, creating a Service requires `uniqueName`, and creating a Participant requires `identifier`.
* An enum parameter contains a value outside the supported set, such as `mode`, `status`, `geoMatchLevel`, or `numberSelectionBehavior`.
* A SID, URI, or date-time field does not match the required format, such as an invalid `ServiceSid`, `SessionSid`, `ProxyIdentifierSid`, callback URL, or `dateExpiry`.
* A string or numeric value exceeds Proxy limits, such as `UniqueName`, `FriendlyName`, `Identifier`, `ProxyIdentifier`, or `ttl`.
* A `proxyIdentifier` was provided for a Participant, but that Twilio number was not already added to the Proxy number pool for the service.

### Possible solutions

* Review the exact parameter named in the warning and compare it with the schema for the Service, Session, or Participant resource you are calling.
* Send only documented values for enum fields. For example, use one of the supported values for `mode`, `status`, `geoMatchLevel`, and `numberSelectionBehavior`.
* Validate identifiers before you send the request. Ensure SIDs use the correct prefix and length, callback fields are valid URIs, and `dateExpiry` is a valid ISO 8601 date-time value.
* Keep request values within documented limits. `UniqueName` must be 191 characters or fewer, `FriendlyName` must be 255 characters or fewer, `Identifier` must be 191 characters or fewer, `ProxyIdentifier` must be 255 characters or fewer, and `ttl` must be greater than 0 and less than 2147483647.
* If you set `proxyIdentifier` or `proxyIdentifierSid` on a Participant, use a Twilio number that is already assigned to the Proxy service's number pool.

#### Additional resources

* [Service resource](/docs/proxy/api/service)
* [Session resource](/docs/proxy/api/session)
* [Participant resource](/docs/proxy/api/participant)