このエラーメッセージに関する原因と対処に関して説明します。
エラーメッセージ(英語)：
invalid_grant
対処
関連リンク
トークンエンドポイント - Amazon Cognito
https://docs.aws.amazon.com/ja_jp/cognito/latest/developerguide/token-endpoint.html
TOKEN Endpoint - Amazon Cognito - AWS Documentation
https://docs.aws.amazon.com/cognito/latest/developerguide/token-endpoint.html
invalid_grant - Amazon Developer Forums
https://forums.developer.amazon.com/questions/166124/invalid-grant.html
Request an access token
https://forums.developer.amazon.com/questions/112810/request-an-access-token-1.html
invalid grant parameter : code
https://forums.developer.amazon.com/questions/63896/invalid-grant-parameter-code.html
invalid_grant redirect_uri during dash LWA
https://forums.developer.amazon.com/questions/58168/invalid-grant-redirect-uri-during-dash-lwa.html
Authorization code returns error : invalid_grant when ...
https://forums.developer.amazon.com/questions/46495/authorization-code-returns-error-invalid-grant-w・・・
Google OAuth “invalid_grant” nightmare ? and how to fix it
https://blog.timekit.io/google-oauth-invalid-grant-nightmare-and-how-to-fix-it-9f4efaf1da35
GoogleのService Account認証に潜む invalid_grant 問題 | infoScoop ...
https://www.infoscoop.org/blogjp/2015/03/10/google_invalid_grant/
oauth - Salesforce OAuth2 invalid_grant: user hasn't aproved this ...
https://salesforce.stackexchange.com/questions/232979/salesforce-oauth2-invalid-grant-user-hasnt-apr・・・