Updating relationship issue

I'm having an issue updating all records of a relationship modal. Instead only one model is updating all records. I need EACH record to be updated.

I have a MODEL which has holds a "retailer" and this model has an hasMany relationship with a "Location" model. The location model belongsTo the retailer model.

The Location model holds Addresses for retailers. Some Retailers have many locations (addresses). I have tried many solutions but cannot seems to get any to work. The only solution that has worked is using first(); which updates the first record, but I need to update all address records.

 public function update(Request $request, $id)
 {
     $location = $request->only(
         'street_number', 
         'street_address',
         'city',
         'state',
         'postcode',
         'country',
         'longitude',
         'latitude',
         'country_code'
     ); 

     $insert = Location::where('id', $id);
     $insert->update($location);

     return Redirect::route('retailers.edit', $id)
        ->withInput()
        ->withErrors($validation)
        ->with('message', 'There were validation errors.')
     ;
  }

via Chebli Mohamed