With a contactless card you always have your ticket already in your pocket! Moreover Tap & Go ® allows you to use your credit card as a monthly subscription. 

Buy your monthly subscription online on Tap & Go - MyAtac with your contactless payment card enabled for online purchases and use the same card to travel with public transport. 

Remember, in this case you cannot use smartphones or smartwatches on which you have digitalised your card, you have to use the same physical card with which you purchased the subscription on the portal.