Hi AlinaKalinina, 

NS does not have subscriptions to travel with discount or for free with the bus, tram or metro. It is possible to order another contract with another company on the same OV-chipcard as your NS contract. But if you have a NS Flex contract, it is important to cancel the bus, tram and metro part of this contract. You can contact our customer service for this. 

Thanks for the answer!  What does it mean to cancel some services?  I have traject vrij.  I thought it was only for subscription trains?

You have NS Flex Traject Vrij. With NS Flex you can also travel on invoice in bus, tram and metro. However, this does not combine well with subscriptions for bus, tram and metro. You need to contact custuomer service to have them disable the bus, tram and metro part of NS Flex. Then you can load a subscription for bus, tram and metro on the card. And you will need to load credit on the card to travel with bus, tram and metro.

my bus overview is not showing

Hey y gardizi. Welcome to the NS Community.

We can't help you with this kind of question here. I'd advise you to contact our customer service for this!