I always get rendered and old version, I cannot save the new version neither Hello Blender Community,

I already checked for this question, and it seems it already has been asked and answered. Still, I none of the answers helped me to fix this problem in my case.

I opened my file (waste floating in the ocean) to add more waste to the scene. Then I want to save it and render it. But pushing the render button it jumps back to the old version and renders the old version. 
To get back to my modified version (where I added more waste) I have to use the CMD-Z combination, because it seems I also cannot save the new version.

In the photo attached I described the problem.
I hope somebody can help me. 
Thank you!


********************* EDIT 1 *************************
I edited the scene again. I put 2 new plastic cups in the scene.
And when I push the render button these 2 cups stay in the scene.
Only the 3 new bottles disappear? 
I duplicated the other 2 bottles to create the 3 new bottles. But why do they disappear when rendering the scene while the new cups stay in the scene?
 

********************* EDIT 2 *************************
Has it something to do with these arrows? 
Because the cups do not have these arrows while the bottles have them.
When you duplicated your bottles, you also duplicated their animation data. After you reposition your duplicates, you also need to overwrite the location and rotation keyframes, or they will jump back to the original position as soon as you hit render or change the frame.