Hi,
For some of the ASA account Get User ACL api is working fine without X-AP-Context in the header. But for some of the ASA account we are getting 403 response code. As per API details X-AP-Context is not a mandatory field. If we provide X-AP-Context for failed ASA account it works fine.
Looks like there some changes in ASA api based on the account that may cause this issue.
Thanks Shankara