Hsn code registration

No such notification issued but there is no other way to declare the details. 

Also there is no relation between ammendment of non-core fields and GSTR returns. You can ammend non core fields  whenever you want.

If I amend goods and services newly from today , it will effect from today onwords right?

Yes. However if you want to change from date within last 1 month, you can also do so.

Thanks,

coz the earlier person applying gst registration in july 2017 he just put a other item such as rice , paddy , but they are doing mobile recharge is the main business. recently i was taken this filing from my side. when I checked those returns filed already are not related to the hsn number. so, need some support coz the official called the dealer regarding this.

You can also apply for non core from 01.07.2017 giving reason that due to oversight wrong goods and services are mantioned under GST certificate

WHERE TO MENTION THE DATE FROM? IF I AMEND STRAIGHTAWAY IT WILL GO TO VERIFICATION ONLY BY TODAY.