I have smart previews but not originals

I have an external hard drive with original photos on it.  I imported as I normally do and started editing them when I noticed that i dont have originals only smart previews.  I have tried to re import the photos but for some reason they won't import (copy or add) So I have all these edits that aren't connecting with original files. I do not know how to re connect these edits onto the originals.  Any ideas?  The photos are on the hard drive and on a back up but I cannot find out how to fix this problem.  I can find info on how to add smart previews but not the originals. But, i am wondering if i build standard previews is that going to fix it? thank you for your help!   Karina