Hi,
I am lost in using iscogen. I need to convert an old dataset isco88 4 digits occupation classification to Isco08 4 digits.

I am using this code it show 0 matched. Is there any mistakes I am doing? Is there any complete Stata codes anyone can share please?

Code:
iscogen iseicodes = isei( bsco3des), from(isco08)

Thanks