$student = [ABC, DEF];

public function getData()
{


     $newData = $newDataId = $newDataStudIds = $DataIds = [];
        foreach ($student as $key => $value) {

            $Ids   = [69, 70 ,71];

            //for above Ids foreach is executed
            foreach ($Ids as $Id) {

                $data = $this->api->request('marks', [
                    'Id'          => $Id,
                    'teacherId'   => 1
                ]);

                if ($data != 'error') {

                    $body = json_decode($data->getBody(), true);

                    foreach ($body['student'] as $student) {
                        $newData[$body['profile']['stud_id']][]   = $student['stud_id'];
                        /* so $newData will contain
                        array(69 => array('0'=>1,'1'=>"2"),
                             70 => array('0'=>2,'1'=>"3"),
                             71 => array('0'=>3,'1'=>"1")
                        )*/
                    }
                }
            }

            $newDataId = array_keys($newData);
            $newDataStudIds = array_values($newData);

            $DataIds = $this->implodeAllArray(',', $newDataStudIds);
            $DataIds = implode(',',array_unique(explode(',', $DataIds)));
            /*
                i want $DataIds = [69] => [1 ,2]
                [70] => [2, 3]
                [71] => [3, 1]

            But this $DataIds return array like
            [69] => [1, 2 ,2 ,3]
            [70]  => [1, 2 ,2 ,3]
            [71]  => [1, 2 ,2 ,3]
            */

        }

}

public function implodeAllArray($glue, $arr){
    for ($i=0; $i<count($arr); $i++) {
        if (@is_array($arr[$i]))
            $arr[$i] = $this->implodeAllArray($glue, $arr[$i]);
    }
    return implode($glue, $arr);
}

i want $DataIds =

    [69] => [1 ,2]
    [70] => [2, 3]
    [71] => [3, 1]

 But this $DataIds return array like
    [69] => [1, 2 ,2 ,3]
    [70]  => [1, 2 ,2 ,3]
    [71]  => [1, 2 ,2 ,3]