I would first try stopping the utrogestan for about 5+ days to start a shed. You may find it takes a few days to get going (it takes me 5 days after stopping it, before I start to bleed and then I stay off it for another 4-5 days until it's done - to let it all come out).
The thing is (I keep trying to explain this)... HRT was designed with tiny pathetic doses of estrogen to offset the worst symptoms. That kind of dose, is unlikely to give you the best health benefits with bone and cardio protection, dementia reduction and all the rest. It just keeps hot flushes away. When you take a tiny low dose of estrogen and a generous whack of progesterone (which is the standard HRT deal), you won't get much uterine lining build up at all and can go onto continuous progesterone and never bleed in post-menopause.
But if you take enough estrogen to see all the health benefits from it (serum levels around 500-600pmol), you are unlikely to not be bleeding. Because estrogen acts throughout the body to cause (for eg) bone to build up, skin cells to turn over and renew - it is growth proliferative, in other words - and it's not going to only do that to your bones and your skin and brain and heart - it's going to do it to you endometrium as well. And what builds up, must come out.
So if you take sufficient E, you are likely to need to have an outlet for the build up even in post-menopause. If you don't schedule a bleed, it will happen randomly and unpredictably and alarm doctors and see you referred for hysteroscopies and biopsies. If you schedule it and it only happens when you stop P, then no one minds.
Unfortunately mainstream health care hasn't quite caught onto this yet and seems to be caught up in the fantasy that women should be able to take decent doses of estrogen in post-menopause and expect not to bleed if they take P continuously. That doesn't make biological sense.