Codeigniter 4 'update' from Controller - codeigniter

Question

I'm so confused...
This function runs OK and doesn't throw up any errors... but it doesn't update the row in my table.
Where have I gone wrong?
Controller:
public function update()
{
$model = new StoreModel();
$model->where('merchant', 'Klip Shop')->set('availability', 'out of stock')->update();
}
Model:
class StoreModel extends Model
{
protected $table = 'shop';
}

Answer 1

It was an $allowedFields issue with the model, hence nothing was 'allowed' to be updated.

Answer 2

Since $model->where('merchant', 'Klip Shop')->get() doesn't return anything, it means that you don't have any data you can update.
You need to insert a row first.
you could use the insert() function, if there is no rows detected
with the merchant name
or
there is the save() function in CI 4.x which either inserts or
updates on duplicate. but to get it to work, you need to set
merchant to unique or use a column with an unique key
please read: Saving Data in CI 4.x
edit: you actually got me confused too:
only now I analized your MCV code:
you should have a controller
public function update()
{
$model = new StoreModel();
$model->update();
}
and a model:
class StoreModel extends Model
{
$db = \Config\Database::connect();
$model= $db->table('shop');
function update(){
$model->where('merchant', 'Klip Shop')->set('availability', 'out of stock')->update();
}
}