how can generate access token

Retrieving Activation Token

To obtain the activation token, the user is required to login with their Apple ID on the following URL:http://gsx[-uat].apple.com/gsx/api/login/.

but above mentioned url is not working today it(http://gsx2-uat.apple.com/gsx/api/login) is directly redirecting to https://gsx2-rno-uat.apple.com/gsx/api/login And 403 Forbidden issue occurring.

It is mentioned under the GSX API uses documentation.

You can check this by login into below mention portal, only if you have access.

https://idmsa.apple.com/IDMSWebAuth/signin?appIdKey=68e1fd1c0c115bb33800e75de65611436b44004b5ad4518de612cd573079c313&rv=16#/