About Credit note

Shoeb Hasan (81 Points)

03 June 2018  
a supplier of mine issued me a credit note, and i took itc for that in 3b, since it was a credit note so i didn't mention it in gstr 1 but my supplier should have mentioned it (because it was sales return for him). but he didn't..
now what should i do? this was from jan 2018 and now the year is also over.. help . thnx