Facebook Social Avatar Problem

Hi,

I enable the social avatar option, but Facebook avatar request (https://graph.facebook.com/****************/picture?type=large) returned OAuth error:

{
   "error": {
      "message": "An access token is required to request this resource.",
      "type": "OAuthException",
      "code": 104,
      "fbtrace_id": "**********************"
   }
}

Is there any work around for this? Thanks in advance.

Regards.