Each Chrono Ticket grants you a set amount of time in the Chrono Mine event. When time runs out, your Super Managers will go into cooldown and you will not be able to interact with the mine unless you use another Chrono Ticket.
If you want to keep playing without being interrupted, you can extend your time in the Chrono Mine by using more Chrono Tickets before your currently active one expires!

The number of Chrono Tickets available is limited and every player gets the same amount of them. Buying new tickets isn't an option, and they won't refill automatically over time. So make each ticket count and plan your moves carefully to aim for a high score!

If you want to replay the current Chrono Mine to get a higher score, you can use Reset Coupons: see "What is a Reset Coupon?"