I am using Pedestal and try to call AWS Cognito idp API with cognitect aws library. Created a User Pool at Cognito, and created new IAM user. I have set up the credential & config files at .aws directory. The AWS CLI call works just fine, and showing the User Pool Information as below: $$> aws cognito-idp list-user-pools --region us-west-1 --max-results 10 { "UserPools": [ { "Id": "us-west-1_uVhjybJkfk", "Name": "XXXXXX", "LambdaConfig": {}, "LastModifiedDate": "2023-01-19T23:09:55.977000-08:00", "CreationDate": "2023-01-19T23:09:55.977000-08:00" } ] } But the from the REPL using Cognitect API: (aws/invoke cognito-idp {:op :SignUp :request {:ClientId "XXXXXXXX" :Username "<mailto:[email protected]|[email protected]>" :Password "Password" :SecretHash (calculate-secret-hash {:client-id "-------" :client-secret "--------" :username "<mailto:[email protected]|[email protected]>"})}}) => {:type "ResourceNotFoundException", :message "User pool client XXXXXXX does not exist.", :cognitect.anomalies/category :cognitect.anomalies/incorrect} Any hints? Thanks in advance.