[Rufio]

Change your code to this and it'll work;

pawn Код:

new Text3D:ranklabel = Create3DTextLabel("Rank", 0x008080FF, 30.0, 40.0, 50.0, 40.0, 0);
    Update3DTextLabelText(ranklabel, 0xFFFFFFFF, "%s", GetPlayerDMRank(playerid));
    Attach3DTextLabelToPlayer(ranklabel, playerid, 0.0, 0.0, 0.7);

You are using a function without passing in the required parameter.