# `invalid_exact_evm_payload_authorization_valid_after`

> The payment authorization is not valid yet. What causes this x402 error and how to fix it.

The payment authorization is not valid yet.

|  |  |
| --- | --- |
| Reported by | the facilitator, during verify |
| Usually fixed by | the buyer |

## Cause

The authorization's `validAfter` timestamp is later than the facilitator's clock.

## Fix

- Buyer: check the system clock; one running ahead causes this.
- Buyer: set `validAfter` to `0`, as the official client does.

## About this reference

Causes are taken from the source of `@x402/evm` 2.31. Other facilitators and later versions may use the same code for slightly different checks. See [all x402 errors](https://x402testendpoint.com/errors).

Source: https://x402testendpoint.com/errors/invalid_exact_evm_payload_authorization_valid_after