php 找出数组中重复的数组

$str="订单编码
SF20220326249392
LZ20220324189853
SF20220326612587
LZ20220401808376
LZ20220401072269
LZ20220401973666
AL20220328244437
LZ20220401690033
LZ20220401006998
LZ20220401217248
EB20220331212841
EB20220331741212
EB20220330321473
LZ20220401507980
LZ20220401107937
LZ20220401827197
SF20220326207532
";
       $str= explode("\r\n",$str);
        $unique_arr = array_unique ( $str );
        $repeat_arr = array_diff_assoc ( $str, $unique_arr );
        dump($repeat_arr);die;