How to remove unwanted mark seams Can you anybody tell me how can I delete these mark seams please? In edit mode I can't find any mark seams but when I unwrap the model there they are! why? Ctrl+E - not working.
Those are pinned UV coordinates, they are not affected by future unwraps. 

Select them and hit Alt+P to unpin. Unwrap afterwards.

https://docs.blender.org/manual/en/dev/editors/uv_image/uv_editing/layout_editing.html