do not know lisence number

i have an adobe package cs4 bought and installed on computer in 2010. i want to dowload it onto new computer. i am having troubles as on the new computer- when going into creative cloud dowload app- i only have an option of buy/dowload free trial.

i do not have my lisence number- cannot track it. only have other bar codes/ a 20 digit code on registration form.

how can i track my lisence down?

thank you