Go to your emails login and search boltiot and check the first last five to sevel mails(mails you got when you were confirming yourself or applying for scholarship or paying for the hardware kit). In one of those emails you will get the course access code. It is the same code you used to access this online training.
Or on the fourth last slide “Important points about the certification test”
there is a link given under ’ I forgot my ‘Course access code’ or delete it then how can I get it again?’ you can check it out, there the course access code is given