Mismatch OF ITC between between my Gstr 3bs

There's a mismatch of itc(Jan'2021) between gstr 3B from my books of account and system generated 3B. Itc as per book is less than system generated. After going through system generated 2B i found that a)some unknown supplier has uploaded invoice in my GSTIN 2)another supplier upploaded August 2020 invoice now(i already availed this itc in August 2020 itself). Now if i file gstr 3b as per my books, there's a red warning box about mismatch. What should I do... suggestion would be appreciated.Thanks for reading.