Why does my home office expense say "not started" and instead all the expenses are carried forward?

Is your self-employment income already zero or negative before you include your home office expenses?

The amount you can deduct for business-use-of-home expenses can't be more than your net income from the business before you deduct these expenses. You can't use these expenses to increase or create a business loss, so TurboTax will automatically carry forward what you can't use on this year's return.