# 20155: Expiration Time In The Future

Log Type: TWILIO

Log Level: ERROR

## Description

The JWT provided to the Twilio API is not yet valid. This typically indicates that the token's valid start time has not been reached.

### Possible causes

* The system clock on the server that generates the token is inaccurate (clock drift), causing the token to appear not yet valid.
* The token includes an `nbf` value that is in the future relative to current time; tokens are not accepted before the `nbf` timestamp.

### Possible solutions

* Correct the server's system time so that token generation uses the current time; then retry the request.
* Remove the optional `nbf` claim or ensure `nbf` is set to a time that is at or before the moment the token will be used.
* Inspect the token to verify time-based claims (`nbf`, `iat`, `exp`) are reasonable and consistent with Twilio's expectations; regenerate the token immediately before use if needed.

#### Additional resources

* [Access Tokens](/docs/iam/access-tokens)
* [20105: Access Token not yet valid](/docs/api/errors/20105)
* [20157: Expiration Time Exceeds Maximum Time Allowed](/docs/api/errors/20157)