There is no error. If you want to have a Gross Margin / Gross Profit Create a group for Cost of Goods sold and move the relevant account under that group. Then create a “New total” and place that under the Cost of Goods sold group and call it something like Gross profit. All these actions are to be done in Settings → Chart of Accounts.
Maybe you should consult the old guides how to set one upunder structuring accounts at:
https://www2.manager.io/guides
I will try that
Thanks alot