Daily work the same every day from 4/1/to 4/6

Each day (past and future) shows daily work of 1800; and in the weekly summary, it also shows 1800 as the work (on the summary by zone - purple number far right); the actual weekly total in the middle of the summary looks correct, as are the actual stats from the workouts each day (but the daily total at the top of each day is wrong).

Do you mind posting a screenshot or two. Tx.

Well, now it changed to 1942 KJ:

Aha. That is a custom fitness plot added to the calendar via Options → Fitness:

And it is a monthly average which is why it is the same on each day.