array elements in callback

I'm making a block with MB Blocks. I'm having trouble with the callback. here's my callback:

function hba_hours( $attributes ) {

    // Fields's data.
    if ( empty( $attributes['data'] ) ) {
        return;
    }

    $prefix = 'hba_blocks_';

    $title = $attributes( $prefix . 'hours_title' );
    $hours = $attributes( $prefix . 'hours' );

    echo '<h4>' . $title . '</h4>';
    return '<p>' . $hours . '</p>';
}

I get a 500 that starts with this:

<b>Fatal error</b>:  Uncaught Error: Array callback must have exactly two elements in /home/customer/www/heartsideb.sg-host.com/public_html/wp-content/plugins/heartside-blocks/heartside-blocks.php:74
Stack trace:
#0 [internal function]: hba_hours(Array)

I don't even know what question to ask here. What's wrong?