if and ifelse problems [duplicate]

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• PHP Parse/Syntax Errors; and How to solve them? 10 answers

I have a trouble with my code, in the structure when something hasn,t a condition get the value of second last else ('no') but it have to get the last else. I´ve cheked my code for a couple of hours and I didn´t see any problem . Some solution or other way for get the results that I hope.

for ($i=0; $i <sizeof($datos) ; $i++){
    if (empty($_POST[$datos[$i]])) {
        $err = "<div class='alert alert-danger'>Rellena el campo " .$datos[$i]."</div>";
    }elseif($datos[$i] == "numero"){
        $datos[1] = $_POST[$datos[1]];
        for ($i=0; $i < $datos[1] ; $i++) {
            if(isset($_POST[$secciones[$i]])){
                $definidas[$i] = $_POST[$secciones[$i]];
            }else {
                $err = "<div class='alert alert-danger'>Rellena todas las Secciones</div>";
            }
        }
    }elseif($datos[$i] == "facebook"||"twitter"||"google"||"instagram"||"correo"){
            if($_POST[$datos[$i]] == "si"){

                if (empty($_POST['di'.$datos[$i]])) {
                    $err = "<div class='alert alert-danger'>Rellena todas las casillas sociales</div>";
                }else{
                $datos[$i] = $_POST['di'.$datos[$i]];
                }

            }else{   
                $datos[$i] =  "no";
            }

    }else {
        $datos[$i] = $_POST[$datos[$i]];
    }
}

and this is my array

$datos = array ('web','numero','slider','vista','facebook','twitter','google','instagram','correo','admin','contrasena');