After years of strong medication, my solution was Melatonin pills.
Confirmed Sleep, Wake Cycle Disorder and it was all down to a simple chemical imbalance. My melatonin was releasing at the wrong times, so I would usually start nodding off at 10am.
After 4 years of utter hell , the fix was simple.
Whenever I start to feel myself slipping again, I spend more time in direct sunlight for a couple of days and it sorts it out. Weird.
Thanks mate but unfortunately not that in my case as I came upon this suggestion before with the result that the neighbours were getting a bit tired of the great haired wrinkly half naked man in the communal garden.
Unfortunately all I got was a nice tan but no improvement in sleep cycles.
One of my internal clocks was knocked off kilter during my time in the Royal Marines some 40 years ago which meant I slept and woke early which was fine. But now I sleep early but only for a brief time.