Newbie (insert won't insert data)

I’ve been editing the cakephp script of a friend.
First of all I edited the view and added a new form input element by using:

$this->Form->input('withdrawal_bitcoin', [
    'label' => false,
    'placeholder' => __('Bitcoin Adress,
    'class' => 'form-control'

After this I added a new database attribute to the users table called “withdrawal_bitcoin”.
Now I opened the signup action and inserted this code:

$user->withdrawal_bitcoin = $this->request->data['withdrawal_bitcoin'];

I tried to run this, but the result is, nothing gets inserted into database. When I use a “die(var_dump($this->request->data[‘withdrawal_bitcoin’]))” inside the controller action I’m able to see the entered value, so the value is not “empty”. Any idea where things go wrong?

I’m assuming the withdrawal_bitcoin field actually exists in the users table (also assuming it’s the users table)?

In cases such as this, most of the time it has to do with validation. Is this field being validated in the model in some ways?

Other than that, can you post the whole signup action?

Oh, and I guess it’s a copy & paste mistake, but after “Bitcoin Adress” there’s no ')