Repeating reminders’ subtasks remain completed rather than reverting to not complete

1 create a reminder

2 set a repeat date etc.

3 click on the “I” in the circle to add subtask(s)

4 scroll down to subtasks and add subtasks

5 complete the task and included subtasks

6 wait the repeat interval

7 check the subtasks. They will be completed. The task will show not completed

this is true on an iPad Pro iOS 18.1

if I look at my MacBook Pro reminders tasks, I cannot see the subtasks in the information window at all. That is MacBook Pro 16 with macOS 15.1

my iPhone SE with iOS 18.1 has the same behavior as the iPad Pro