Hi,
So it can be a serious pain to cut paste into a container. It just hates doing it, but it does work.
its super important to go slow.
First, make a copy of your screen (duplicate it)
Now select the item you want to cut and cut it
Now select the container. here is where it gets silly. When you first try you THINK you did it, but in fact you didn't.. yeap you didn't. so when you paste it goes into the form.
When you select it, verify that the container is selected (it won't be , not really). Select it again and make sure to try to do it by clicking on the Edges of the container or hover over it, unti you see the MOVE icon change, then click that, then paste it.
It will work. Its a pain sometimes, but it will. Dragging and dropping it via the Tree doesn't work really.
My suggestion for Clone/duplicating the screen is 2 part
1) so you dont mess up your screen
2) so you can practive.
It will work. I've had the same issue over and over and over, with containers or galleries etc.