Insert return false but inserts succesfully

I'm wreaking my brain, unable to figure this one out. 
I have the folowing code:

PHP Code:

if ($klantenModel->insert([
                        'id' => $this->request->getPost('id'),
                        'naam' => $this->request->getPost('naam'),
                        'woonplaats' => $this->request->getPost('woonplaats')
                    ]))
                {
                    return redirect()->to($_ENV['app.baseURL'] . 'klanten')->with('success', 'Gelukt.');
                }
                return redirect()->to($_ENV['app.baseURL'] . 'klanten')->with('error', 'Fout.'); 


What happens is dat the insert does what I expect (it inserts the data without a glitch), yet it returns false. And I can't figure out why. It doesn't insert empty columns, the data types of the respective columns in the database are correct (int for id and varchar(100) for the others). 

I hope you guys can help me figure out what the cause of this behavior is.

Try thios and see what your query is looking like.

PHP Code:

$db->insertID();
$db->getLastQuery(); 


Please show it here.

What did you Try? What did you Get? What did you Expect?

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