Are they adjusting income taxes

Typically, the reasons for not qualifying for the Earned Income Tax Credit (EITC) are the income was not "Earned" income (see below) or the taxpayer doesn't meet the special rules for filing as Married Filing Separately (see below).  

Here is a link with the basic qualifying rules.

Earned income includes:

• Wages, salary or tips where federal income taxes are withheld on Form W-2, box 1
• Income from a job where your employer didn’t withhold tax (such as gig economy work) including:
  • Driving a car for booked rides or deliveries
  • Running errands or doing tasks
  • Selling goods online
  • Providing creative or professional services
  • Providing other temporary, on-demand or freelance work
• Money made from self-employment, including if you:
  • Own or operate a business or farm
  • Are a minister or member of a religious order
  • Are a statutory employee and have income

Earned income does not include:

• Pay you got for work when you were an inmate in a penal institution
• Interest and dividends
• Pensions or annuities
• Social Security
• Unemployment benefits
• Alimony
• Child support

You can claim the EITC if you are married, not filing a joint return, had a qualifying child who lived with you for more than half of 2023, and either of the following apply.

• You lived apart from your spouse for the last 6 months of 2023, or
• You are legally separated according to your state law under a written separation agreement or a decree of separate maintenance and you didn't live in the same household as your spouse at the end of 2023.