failed to connect to AWS globus endpoint

I used to be able to successfully connect to the endpoint and transfer data from/to S3 buckets. But I haven't been able to connect to it since several days ago. The technical support from Globus said I should reach out the admin of aws endpoint to resolve the issue. The aws endpoint info is:

endpoint: Amazon Web Services S3 Collection (All Regions) UUID: 9349594d-b602-45da-8568-17cf96d0624f host: scofri @ amazon.com

The error I got is:

Command Failed: Error (connect) Endpoint: Amazon Web Services S3 Collection (All Regions) (9349594d-b602-45da-8568-17cf96d0624f) Server: 3.139.64.86:443 Message: Could not connect to server Details: globus_xio: The GSI XIO driver failed to establish a connection via the underlying protocol.\nglobus_xio: Unable to connect to 3.139.64.86:443\nglobus_xio: System error in connect: Connection refused\nglobus_xio: A system call failed: Connection refused\n

Could you help me to troubleshoot this? Thanks.