I am using Turbo tax Premier + Business. was unable to netfile the return since it is asking for 15 digit business number and I only have a 9 digit since I do not remit GST, it is under $30000. tried RT001 or Rc0001 after and it prohibits me from netfiling
Business numbers are 15 digits. Have you had a Business before? If this is a second business it could be RT0002.
In your description your RT only had two zero's not three.
You can read more about it in this TurboTax article: https://turbotax.intuit.ca/tips/a-guide-to-business-numbers-6211