Magento has added new features called GraphQl from the Magento 2.3 version.
While working with Magento GraphQl feature for the generating customer token, you might be facing the error,
The account sign-in was incorrect or your account is disabled temporarily. Please wait and try again later
An error is displayed in spite of the valid email and password provided in the mutation. This error will be fixed by providing a store view code to the mutation.
How to fix the account sign-in was an incorrect error in GraphQl?
Generally, We can be facing an error while Magento with the multi-website feature enabled, customer email and password are correct but you forgot to provide store view code in the request.
You have to pass your store view code to the header of the GraphQl request to fix the error.
I have added my store view code as international to generate customer tokens with a valid email and password with GraphQl.
You can read to Generate Customer token GraphQL Query Magento 2?