Eloquent relationship returns null, but a similar one is fine - lumen

Question

Using Lumen 5.5.2 and illuminate/database v5.5.17.
I have 3 models set up, where one belongs to the other 2. So Quote, has an area, and a depot.
The relationship with the depot works as expected, the area returns null.
for example
$quoteModel = new Quote();
$quote = $quoteModel
->with('area')
->with('depot')
->where('id', '=', $id)
->first();
echo 'depot id : ' , $quote->depot->id , "<br>\n";
echo 'area id : ' , $quote->area->id , "<br>\n";
The depot id will be echoed, the area will cause an error because it is not an object.
Passing the models names as an array ->with(['area', 'depot']), or just requesting area (either method) does not fix it.
Quote.php
namespace App\Models;
use Illuminate\Database\Eloquent\Model as EloquentModel;
class Quote extends EloquentModel {
protected $table = 'quotes';
public function area() {
return $this->belongsTo('\App\Models\Area', 'area_id', 'id');
}
public function depot() {
return $this->belongsTo('\App\Models\Depot', 'depot_id', 'id');
}
}
Area.php
namespace App\Models;
use Illuminate\Database\Eloquent\Model as EloquentModel;
class Area extends EloquentModel {
protected $table = 'areas';
public $timestamps = false;
public $incrementing = false;
public function quotes() {
return $this->hasMany('\App\Models\Quote', 'area_id', 'id');
}
}
Depot.php
namespace App\Models;
use Illuminate\Database\Eloquent\Model as EloquentModel;
class Depot extends EloquentModel {
protected $table = 'depots';
public $timestamps = false;
public $incrementing = false;
public function quotes() {
return $this->hasMany('\App\Models\Quote', 'depot_id', 'id');
}
}
If I create a parse error in Area.php the script will fail, proving it is being included.
I have a listener set up so I can log the queries, and they show up just fine.
select * from `quotes` where `id` = 99192 limit 1
select * from `areas` where `areas`.`id` in (072)
select * from `depots` where `depots`.`id` in (07)
If I run the area query manually it returns the row I expect.
I tried changing the name of the area relationship, and it doesn't help.

Answer 1

So the missing piece of the puzzle, was that this project is setup up against a legacy database as part of updating an existing web app.
Turns out that there was some datatype inconsistency; I found this out when I could successfully link another model to area with no issues. The field for the area_id is normally a zero filled int, but for some reason on the quotes table it was a char; so the data looked correct when browsing in adminer, and worked when copied and pasted, but did not match up somewhere in Eloquents internals.
Changing the datatype on the table fixes the issue.