php - Lumen AND OR conditions in Where clause -

i trying run following query in lumen framework:

select * user (username = $username or email = $username) , password = $password , flag = 1; 

my lumen code:

$login =  user::where('pass', '=', md5($pass))                ->where('flag', '=', $flag)                ->where('username', '=', $username)                ->orwhere('email', '=', $username)->first(); 

somehow code return true , bypass login. wrong in query?

when remove orwhere query works perfect username.

if want group 2 conditions (username , email) single condition (surrounded parenthesis), have this:

user::where('pass', '=', md5($pass))     ->where('flag', '=', $flag)     ->where(function ($query) use ($username) {         $query->where('username', '=', $username)               ->orwhere('email', '=', $username);     })->first(); 

here documentation on advanced conditions laravel query builder (which lumen uses).