@christinarossetti39 A couple of things....
Missing 2 cycles doesn't mean your periods have stopped (for good.)
This is often how it goes- miss a couple, then back to normal for a few months, then miss another few, or cycles get closer together or further apart.
I always take it at night, but wonder if there's been more than 24 hours sometimes
Do you mean you skip a night? Or it's only an hour or so difference?
Skipping a whole day can cause early bleeding, in some women, especially as Utrogestan is poorly absorbed sometimes.
But my guess is that it's your own cycle that's come back and the utrogestan isn't controlling it enough.
One way to get more absorption is to either take it with food (so, close to a snack or a meal as this doubles the amount getting into the blood stream) or using the capsule vaginally, which gives a higher absorption.
I doubt your GP will know anything more unless they are specifically HRT trained through a BMS course.