Unable to upload files to Digital Ocean Space using .Net Core app

Dears

My application is trying to upload files to DO Space using the code mentioned here:

https://www.digitalocean.com/community/questions/uploading-file-to-do-spaces-using-aws-sdk-net-net-core

Unfortunately, it didn’t work, we added the following modifications to the code: “FilePath = filePath” became “InputStream = fileToUpload.Stream”

But still, we are facing the same exception, the exception is as follows:

System.Net.Http.HttpRequestException: The SSL connection could not be established, see inner exception. —> System.Security.Authentication.AuthenticationException: Authentication failed, see inner exception.

The exception occurs in the following line: fileTransferUtility.Upload(fileTransferUtilityRequest);

Please note that we are using .NET Core to run our application.

Kindly please help if there is anything that can be done to solve this issue.

BR, Mohamed Shlibik