WTSQueryUser Token returning Error code: 1314

Question

I want to fetch an access token of a logged in user using WTSQueryUserToken(), but it returns error code: 1314.

My code for reference:

DWORD sessionId = -1;
DWORD sessionCount = 0;
WTS_SESSION_INFOW* pSession = NULL;
if (WTSEnumerateSessionsW(WTS_CURRENT_SERVER_HANDLE, 0, 1, &pSession, &sessionCount))
{
    if (pSession != NULL)
    {
        for (int i = 0; i < sessionCount; i++)
        {
            sessionId = pSession[i].SessionId;
            WTS_CONNECTSTATE_CLASS wts_connect_state = pSession[i].State;
            if (wts_connect_state == WTSActive)
            {
                HANDLE currentToken;
                if (WTSQueryUserToken(sessionId, &currentToken)) {
                    printf("Access token is obtained \n");
                }
                else
                {
                    printf("WTSQueryUserToken : failed - %d\n", GetLastError());
                }
            }
        }
        WTSFreeMemory(pSession);
    }
}

I have confirmed that the application runs with LocalSystem account privilege and SE_TCB_NAME privilege is already enabled for it.

I confirmed the account by using the following code:

HANDLE process = GetCurrentProcess();
HANDLE processToken;
BOOL openTokenRet = OpenProcessToken(process, TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &processToken);

SID returned by the process token is S-1-5-18

Also, I have checked the privileges enabled for the SYSTEM account by using "whoami /priv" and got to see that SeTcbPrivilege is enabled for the same.

I want to know if any other privilege is required, or anything I am missing here, to get the token using WTSQueryUserToken().