I think I explained bad… (sorry, I dont know english well)
I have a model with multires
This model is symmetric, so I wanted mirrored UVs to lay on top of each other, so it will be easy to draw textures, because the left and the right parts will have same texrure position (on top of each other). So I duplicated my model, deleted half and added a mirror modifier. And applied modifier( You can see that now I have half’s on top of each other)
But then I turn on multires and it looks like that (greeen was mirrored and blue is basic model)
So I decided to transfer UVs from green to blue, but this window popup
So the models are the same, I don`t know why copy UV map not work.