Okay, first things first. Notary or certified true copy of any document unless done in Canada carries NO weightage for VO, because, well, your own country's notary are not under Canadian legal jurisdiction. So, give the VO what they ask for and nothing else in substitute, it will just confuse them.
Given that it was a copy that you submitted might have triggered that particular response. There is NO way of knowing that unless you get the GCMS notes which takes 30 days. So, you cannt do it right now.
Now, most of IELTS centre etc capture your picture and fingerprints which can actually authenticate your identity. Another chance is that your physical appearance has undergone some significant change. Like you picture in your primary photo id, photo sent to IRCC and your TRF are significantly different. I know situations like this have arisen for few folks elsewhere and it was due to a particular software being used by visa offices.
What you need to include is a copy of your original TRF (as per IRCC specs) and also a statement if available from IDP or BC about your TRF.