On the public generic Passenger App, the company that appears as the first option is the closest available vehicle. But when you click on the choices, this will open a list of all the options or bookable companies. The order is according to pricing, lowest offer on top.
If you would like to have a booking form that is only for your company profile(s) we would recommend looking into the rebranded Passenger App. You can find more information here: https://app.taxicaller.net/apps/rebranded-apps/overview
There’s also a free private booking channel on the web where you can create your own embedded booking form for your website from the admin panel: https://app.taxicaller.net/apps/online-booking/embed