From the article:

The Fukuoka Regional Taxation Bureau announced on April 1 that the popular artist behind The Apothecary Diaries manga, Nekokurage, had been charged with violating the Income Tax Act on February 29, 2024…NHK adds that according to a source close to the investigation, Nekokurage was aware of her duty to file a tax return but had said, “I was so busy with the series that I didn’t have time to talk to a tax accountant.”

once she was made aware by the tax office, she immediately paid the full amount, extra tax, and non-declaration tax. She’s now working with an accountant to pay taxes properly