Incorrect Sleep Duration recorded

My sleep duration stats are all right (using Instinct 2 too):

How are your Bed & Wake Up times set? Do you use to stop the Sleep Mode (when it does not stop automatically), and review the Morning Report when you wake up? Did you change locations with different time zones on the concerned days?

Thanx for the response but it has nothing to do with those items you mentioned as the majority of sleeps are recorded fine. 

Yes, it may have a relation. If you wake up in the morning, usually the watch detects it automatically, but when it happens that it does not detect it, the watch's display stays in the sleeping mode, and you may notice it. You can then interrupt the sleeping mode by pressing the GPS button.

And having the bed & wake up time set too wide may lead to sleep detected over two days. The best is keeping the time setting just a bit wider than your typical sleep times. I have it set from 22 to 10, while I typically go to bed after midnight, and wake up around 8. When I wake up, I quickly glance over the Morning Report, scroll to the bottom of it, and enter the standard watch face (no more the sleep mode watchface). Occasionally it happens that I have to interrupt the sleep by pressing the GPS button, before being able to scroll through the Morning Report, and then enter the standard watchface. And as you see, I get correct sleeping data.

Thanks Trux but I have turned off the morning report - my sleep settings are 9pm-6am so shouldn't be a problem and if you look at the screenshot I attached to my first post you will see sleep data missing before it gives me a 'double' duration