Bugged achievement?

Hey all! Quick question for you more seasoned players.

Just beat the spider queen freja and lit her bonfire after and teleported back to the hub. Problem is no achievement popped for doing this? I've run back through multiple times and used the bonfire again and again to try and get it to pop but nothing. Any pointers out there or will I need to do this on ng+ now? Gunning for 100% completion for ng+ is already guaranteed but just curious if this is fixable.

Thanks!