You are responsible for any fines or tickets you get while you are renting the car, just as you would be in your own car. When you drop your car off, please let the car rental company know about any tickets or fines you've incurred.
Timing-wise, as driving and parking fines usually take a while to come through, you may not be charged for fines until after you have dropped off your car. The car rental company will let you know if you've incurred any fines you did not know about. They'll manage the fines and charge your credit card. They may also charge you an administration fee.
You cannot pay for tickets or fines you incurred via Travel+, as such violations are considered private & confidential. Since many countries impose great importance to privacy protection, this aspect of information won't be made available for us. Instead, the car rental company should be able to provide you further assistance with it.