How can I get the original Sri Lanka Railways train ticket?

The 12GO voucher can be shown as printed or screenshot on a suitable electronic device, along with the passport at Stef Lanke, Office No. 7 in the Welikada Plaza Building.
GPS Coordinates 6.9092441,79.8954407**
Monday to Saturday 9:30 – 18:30, Sunday 10:00-13:00.
The Rajagiriya bus stop is a 200m walk from the office.
The public buses that stop here are 144, 176, 177, 171, 174, 175.

Tags: Sri Lanka Railways

OK

I don't have a booking number. I have not purchased a ticket yet.