[Dignity]

I was able to spawn a crane successfully using this:

pawn Код:

#include <a_samp>
#include <zcmd>
#include <streamer>

new CraneObject;

CMD:addcrane(playerid, params[])
{
    new Float:X, Float:Y, Float:Z;
    GetPlayerPos(playerid, X, Y, Z);
    CraneObject = CreateDynamicObject(1378, X, Y, Z, 0.00, 0.00, 0.00, 0, 0, -1, 300.0);
    
    SendClientMessage(playerid, -1, "Spawned crane object!");
    return 1;
}

CMD:destroycrane(playerid, params[])
{
    DestroyDynamicObject(CraneObject);
    return 1;
}

Not sure why it won't work for you. Make sure you move in order to see the object.