My tasks are missing (Today counter shows a count but no tasks appear)

A task can be due today while its start date or time is still in the future. Smart Scheduling can hide it until it is time to start.

Check the clock-shaped button on the sort bar, if shown, and use it to reveal scheduled tasks. If the task appears, its start date explains why it was hidden.

The count beside a list and the badge on 2Do's app icon are separate counts. In the current iPhone, iPad, and Mac apps, the Today-based app badges follow scheduled-task visibility too: tasks with future start times do not count while scheduled tasks are hidden. Other Today settings can also affect the result. See Why does the app icon badge show a different count?.