'datetime', 'rejected_at' => 'datetime', ]; public function user() { return $this->belongsTo(User::class); } public function plan() { return $this->belongsTo(Plan::class); } public function approver() { return $this->belongsTo(User::class, 'approved_by'); } public function rejector() { return $this->belongsTo(User::class, 'rejected_by'); } }