How to claim unclaim itc of 2018-19 and where we show in gstr 1 and 3b return?

Abizer Kothari (TPA) (17 Points)

01 August 2019  

Sir,

I am accountant and I forgot some 2018-19 bills to enter in 3B return, Can I claim input of these bill now and where and which form should be submitted and upto what date?