Nope Bro. I think it's impossible. There may be some problem in the booking system.
Again I would suggest to visit nearest Booking office in person, preferably Booking office near Railway Station ASAP to have your seats and booking confirmed.
Railway Station walay booking offices p quota zyada hota hai, you have more flexibility there.
Secondly, in Ramadan, log kamm safar kartay hain, but jaisay jaisay Eid aanay wali ho gee, and uss k ba'ad, rush barhta jata hai and sometimes tickets nai miltay.
If you will be travelling near Eid or within 10-15 days after Eid, you should immediately rush.
I have seen it many times myself, k booking offices mein aesa b hota hai; aap queue mein lagay hotay hain and jub takk aapki bari aati hai, almost all the seats have been booked / sold.
It mostly happens on Lahore-Karachi routes and normally On Eids / Special Occasions / Holidays.
Meray sath khudd 2-3 baar aesa ho chuka hai, even on Lahore-Islamabad route and in normal routine days.
AC sleepers mein b acha khaasa rush hota hai. So better, to rush to the booking office.