Error: Primary production and/or Non-primary production deferred losses amount incorrect.
Solution: To resolve the issue:
1. Check these item the "loss type", must set to "8 - Loss must be deferred"
2. Check the item "I" or "H" amount.
Note that, item "I" is loss for the current year, and item "H" is loss from prior year.
Related article: How to use Deferred Business Losses (Carried forward Loss) in Individual Tax Return (ITR)
Question: If the taxpayer is not operating the business (where the business had a non-commercial loss in 2020). If there is no business activity in 2021, then I suppose the only reason to carry the non-deferred loss through from prior year is to reach a new grossed-up value.
Answer: ie, it's only useful if there is business activity for the given business in 2021. If the business restarts in 2022, simply include the 2020 non deferred loss as an opening balance in that year.