I love the new feature of being able to see reminders in my calendar but the reminders have been duplicated and I am unable to edit or delete the duplicates. Also, in the health app settings > data access and devices: the this of devices I can link to the health app lists each device many times. For example: “apple watch” is listed more than ten times. “iphone” is listed at least 20 times. Etc.
IOS18 Problems with duplications
You should probably raise these as bugs in the usual way. They won't really get progressed if they're only posted in these Developer Forums.
You need to raise each issue you find separately at https://feedbackassistant.apple.com/ You can post the FB numbers here if you want, so that others can link to them.