Because the word SERIES ? It won't be fixed, it has been that way forever. I have a R9 290...it is listed as R9 200 SERIES. A HD6970 is listed HD6900 SERIES....etc
All R9 200 series card from the R9 270 through to the R9 295x2 will read this way. This is the Series number and not the model of the card itself.
From the screenshots you sent the Device ID shows correctly that it is a Asus R9 270 OC card. You don't need to worry about it showing which model it is.