AWS Authorizaion Header v4 Signature Generation

Hello,
I am just wondering if it would be possible to receive any additional information on how the AWS signature is generated using the Authorization fields provided in the Postman Desktop application? I am able to receive a response from AWS using the POSTMAN desktop application, but when I attempt to manually generate an AWS v4 signature according to the instructions here: https://docs.aws.amazon.com/general/latest/gr/sigv4_signing.html, I always receive the same error message: “The request signature we calculated does not match the signature you provided. Check your AWS Secret Access Key and signing method. Consult the service documentation for details.” Any information would be much appreciated.

If it is if any help, here’s the code that we have written to do AWS auth: https://github.com/postmanlabs/postman-runtime/blob/develop/lib/authorizer/aws4.js