Bills are now paid as you progress through months. In the original 2020 release, we left the billing system in place but didn't make it count towards game progress as the original game was month specific instead of this version that's progressing throughout the year.
Now, the timeline reflects when a new month has started. If you haven't paid the bills, they will be automatically deducted from your bank account. If you don't have the money, you will go into debt.