Salam.
You can still pay them through epay app even if the due date has long gone.
I saw some news online that a guy was caught in Lahore driving a car that had violations of around 16000 Rs and he was impounded. That made me check e-challans against my name and turned out I had 3 pending challans as well. 2 for myself and one for the driver. The driver one even dated back to oct 2020 while mine were from Jan 2021. I paid them by generating PSID through epay app and then used the code to pay via online banking. There was no surcharge amount for failing to make the due date.
