# `invalid_exact_evm_scheme`

> The payment or the requirements name a scheme other than `exact`. What causes this x402 error and how to fix it.

The payment or the requirements name a scheme other than `exact`.

|  |  |
| --- | --- |
| Reported by | the facilitator, during verify |
| Usually fixed by | the buyer or the seller, depending on the cause |

## Cause

The `exact` EVM verifier received a payload or requirements whose `scheme` is not `exact`.

## Fix

- Make sure the payload's accepted option and the seller's requirements both say `scheme: "exact"`, or route other schemes to a facilitator that supports them.

## 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_scheme