Starting a process that can operate in Windows lockscreen

Question

I want to create a process that can operate in lockscreen. SendInput to be more precise, I will enter the password simulating keystrokes to log on to user when the screen is locked

When I start the SendInput code delayed(to have time to lock user) it doesn't do anything.

So I want to create a process, preferably using CreateProcessAsUserA, that can operate in lockscreen.

Here's what I've tried:

int main()
{

    Sleep(4000);
    
    LPCTSTR lpApplicationName = L"sendInput.exe";
    LPTSTR lpCommandLine = NULL;
    LPSECURITY_ATTRIBUTES lpProcessAttributes = NULL;
    LPSECURITY_ATTRIBUTES lpThreadAttributes = NULL;
    BOOL bInheritHandles = FALSE;
    DWORD dwCreationFlags = CREATE_NEW_CONSOLE;
    LPVOID lpEnvironment = NULL;
    LPCTSTR lpCurrentDirectory = L"";

    STARTUPINFO si;
    PROCESS_INFORMATION pi;
    ZeroMemory(&si, sizeof(STARTUPINFO));
    si.cb = sizeof(STARTUPINFO);
    ZeroMemory(&pi, sizeof(PROCESS_INFORMATION));

    //get lockscreen user token
    HANDLE hToken;
    if (!WTSQueryUserToken(WTSGetActiveConsoleSessionId(), &hToken))
    {
        printf("WTSQueryUserToken failed with error %d\n", GetLastError());
        return 1;
    }

    //start process using CreateProcessAsUserA
    if (!CreateProcessAsUser(hToken, lpApplicationName, lpCommandLine, lpProcessAttributes, lpThreadAttributes,
                               bInheritHandles, dwCreationFlags, lpEnvironment, lpCurrentDirectory, &si, &pi))
    {
        printf("CreateProcessAsUserA failed with error %d\n", GetLastError());
        CloseHandle(hToken);
        return 1;
    }

    //close handle
    CloseHandle(pi.hProcess);
    CloseHandle(pi.hThread);
    CloseHandle(hToken);

    return 0;
}

But this code is giving me error with WTSQueryUserToken(WTSQueryUserToken failed with error 1314) and I'm not really sure everything else is fine

Here's what's going on in sendInput.exe(I've used qt a bit here to create a map to store key WORD's, didn't feel I need to add it to tags):

void sendPassword(){

    //Map to store keys as char-WORD
    QMap<QString, WORD> keyMap;

    keyMap["Enter"] = 0x0D;

    keyMap["0"] = 0x30;    keyMap["1"] = 0x31;    keyMap["2"] = 0x32;    keyMap["3"] = 0x33;
    keyMap["4"] = 0x34;    keyMap["5"] = 0x35;    keyMap["6"] = 0x36;    keyMap["7"] = 0x37;
    keyMap["8"] = 0x38;    keyMap["9"] = 0x39;

    keyMap["A"] = 0x41;    keyMap["B"] = 0x42;    keyMap["C"] = 0x43;    keyMap["D"] = 0x44;
    keyMap["E"] = 0x45;    keyMap["F"] = 0x46;    keyMap["G"] = 0x47;    keyMap["H"] = 0x48;
    keyMap["I"] = 0x49;    keyMap["J"] = 0x4A;    keyMap["K"] = 0x4B;    keyMap["L"] = 0x4C;
    keyMap["M"] = 0x4D;    keyMap["N"] = 0x4E;    keyMap["O"] = 0x4F;    keyMap["P"] = 0x50;
    keyMap["Q"] = 0x51;    keyMap["R"] = 0x52;    keyMap["S"] = 0x53;    keyMap["T"] = 0x54;
    keyMap["U"] = 0x55;    keyMap["V"] = 0x56;    keyMap["W"] = 0x57;    keyMap["X"] = 0x58;
    keyMap["Y"] = 0x59;    keyMap["Z"] = 0x5A;

    password = "1234";

    //Initialize inputs array.
    INPUT* inputs = new INPUT[password.length()*2] {};


    for(int i=0; i<password.length(); i++){

        //Add password to inputs array char by char, key down and up.
        inputs[i*2].type = INPUT_KEYBOARD;
        inputs[i*2].ki.wVk = keyMap[(QString)password[i]];

        inputs[i*2+1].type = INPUT_KEYBOARD;
        inputs[i*2+1].ki.wVk = keyMap[(QString)password[i]];
        inputs[i*2+1].ki.dwFlags = KEYEVENTF_KEYUP;
    }


    //SendInput, send inputs array.
    SendInput(password.length()*2, inputs, sizeof(INPUT));

    //Delete inputs array.
    delete[] inputs;
}

It would help a lot if you can show a code example, or another solution to this problem. Thanks in advance.