Sorry to hear that. My security check even didn't start after 28 months. It only has been passed after 2.5 years of waiting.I got my CSIS note today (not GCMS note from IRCC or CBSA) to understand what happens to my Security Check.
They sent the note via hardcopy mail within 1 week!!
But sadly, there is not much information. It says:
Security Assessment/Advice (CSIS PPU 005) - A search of this bank was conducted and no personal information concerning you was located.
I guess Security Check is not even started