public function toArray(): array
    {
        $problem = [
            'status'   => $this->getStatusCode(),
            'title'    => $this->getTitle(),
            'detail'   => $this->getDetail(),
            'type'     => $this->getType(),
            'instance' => $this->getInstance(),
        ];

        // Required fields should always overwrite additional fields
        // Use array_filter to remove empty fields in the default fields
        // And don't array_filter $additionalData in case there is a bool = false value
        return $this->mergeArrays(array_filter($problem), $this->additionalData);
    }