CheckboxList selecting everything

Solved the first issue by defining the data structure:

public ?array $data = [
    'accessToken' => '',
    'selectedProducts' => [],
];

public ?array $data = [
    'accessToken' => '',
    'selectedProducts' => [],
];

public ?array $data = [
    'accessToken' => '',
    'selectedProducts' => [],
];

public ?array $data = [
    'accessToken' => '',
    'selectedProducts' => [],
];

Can't get the submit button to do anything though