In using the native calendar app, and viewing the calendar in monthly view, I notice that today (the 31st of October) doesn’t show in October monthly view, only in November’s. Also, when clicking the “Today” button, it takes me to the October monthly view, but the last day on the calendar is showing as the 30th.
Can you add a screenshot?
Please check GitHub issues. There are always people working on calendar app, maybe it has been reported already or even better it is in the work.