# 20157: Expiration Time Exceeds Maximum Time Allowed

Log Type: TWILIO

Log Level: ERROR

## Description

This error occurs when the expiration time used while creating an Access Token `JWT` exceeds 24 hours, which is the maximum allowed lifetime. This behavior is documented on the error page and the Access Tokens overview, which states tokens are "configurable for up to 24 hours."

### Possible causes

* The `ttl` parameter provided when generating the Access Token is greater than 86400 seconds (24 hours). The Access Tokens overview sets a 24-hour maximum and specifies `ttl` is expressed in seconds.
* The token's `exp` claim is set so that its lifetime exceeds 24 hours relative to issuance; Access Tokens are `JWT`s that include an `exp` claim as shown in Twilio's examples.
* Passing time values in milliseconds instead of seconds for `ttl`, inadvertently creating a value above the 24-hour maximum. Twilio materials indicate `ttl` is in seconds and blog guidance notes the maximum must be given as 86400 seconds.

### Possible solutions

* Set the Access Token `ttl` to a value at or below 86400 seconds, and in general keep it as short as feasible for your application (best practice noted by Twilio).
* If you manually construct tokens, compute `exp` so that it does not exceed 24 hours after issuance, or rely on the helper to set `exp` based on `ttl`. Twilio's examples show the `exp` claim and parameterization for `ttl`.
* Ensure you are providing `ttl` in seconds, not milliseconds; for example, 3600 for one hour or 86400 for the maximum. Twilio documentation specifies `ttl` is in seconds, and the Twilio blog reiterates the 24-hour limit as 86400 seconds.
* Implement short-lived tokens with periodic refresh in clients where applicable; Twilio recommends shorter token lifetimes and details token refresh patterns (for example, in Sync SDK guidance).

#### Additional resources

* [Access Tokens](/docs/iam/access-tokens)
* [Create Access Tokens for Conversations](/docs/conversations/create-tokens)
* [Best Practices for Building with Sync SDKs](/docs/sync/sdks-best-practices)