You are posting in an old already-answered thread from 4 years ago on a completely different topic, which was about preparing Schedule C for the self-employed.
You should start your own new thread at the link below so it will show up to the whole forum as needing help.
<a rel="nofollow" target="_blank" href="https://ttlc.intuit.com/questions/new">https://ttlc.intuit.com/questions/new</a>
When you go to the form at the link, the first box is for a summary of your question, like a title, and is limited to 170 characters.. If you need more room, lower on the form you will come to another box with plenty of room to enter details. This is a public Internet forum, so don't post any personal info.
Here is the link for the Schedule C instructions. We can't look it up for you but the principal business codes are listed on pages 16-17: http://www.irs.gov/pub/irs-pdf/i1040sc.pdf
Note that if your business can’t be classified, enter 999999 as the principal business code.
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