Amendment issue.

hello sir/madam

for instance there is a Inv No. 200 filed in Dec-20 return amounted Rs.1,00,000

client says that the invoice is a cancelled invoice an we were entered wrongly in tally and cancelled the same in tally.

So, We amended that invoice in Jan-21 and entered the amount as Rs. 0 and and applied in 3B as well.

now my question is.,
1. is there is any problem with above method ?

2. As it is an cancelled invoice we cannot issue credit note as well right ?

please post your suggestion.
thank you.