Sandbox API response empty with status code = 500

Hi,
I hope this message finds you well.

I'm using sandbox token for API v2024.09 to save addresses and get rates after filling up all required fields and processing the request. I get the response with status code is 500.
Please help me check this issue and let me know if I can use the sandbox token to create a shipment and pick it up. As I know from the previous version (specifically v1.0) I can't create it with a sandbox.

Another issue is that I can't find sandbox token when adding a new integration with the type option = "I'm developing a custom integration." for API Version 2024-09 and newer. After creation, it only shows the product token.