Amazon S3 expert for guidance on file upload error -- 2

Hi... We're trying to integrate an api in our wordpress site... One of the tasks require is to upload our files to a PRESIGNED AMAZON s3 url in the api owners S3 account. We are facing issues in uploading to presigned url and getting the following error Error executing "PutObject" on "[login to view URL]"; AWS HTTP error: Client error: `PUT [login to view URL]` resulted in a `403 Forbidden` response: <?xml version="1.0" encoding="UTF-8"?> <Error><Code>SignatureDoesNotMatch</Code><Message>The request signature we calcul (truncated...) SignatureDoesNotMatch (client): The request signature we calculated does not match the signature you provided. Check your key and signing method. - <?xml version="1.0" encoding="UTF-8"?> <Error><Code>SignatureDoesNotMatch</Code><Message>The request signature we calculated does not match the signature you provided. Check your key and signing method.</Message><AWSAccessKeyId>AKIA6KLT5FIQEJ2LSMJT</AWSAccessKeyId><StringToSign>AWS4-HMAC-SHA256 20220127T084418Z 20220127/us-east-1/s3/aws4_request 4812d8de6bd7ded336325dcb92d16297d482e8121a107bf48a09f919f9b82597</StringToSign><SignatureProvided>e4a29cd814f65ef29704b1a51ace611fadd21bda4c7dd91b6b885cd26223af85</SignatureProvided> Anyone having ideas on fixing it is most welcome..