The new editor is acting funny

There is some sort of bug in the new editor which doesn’t enable me to continue working on the platform - I designed an header about a week ago. Everything was fine and it looked great when I viewed it both at the tablet and mobile breakpoint. I opened the site again this morning and I can’t make the header to appear any more on these breakpoints (I see this element when I look at the Layers section, but a diffrent section - which I have deleted appears instead, and I can’t move it or delete).
The lay-outing in tablet and mobile breakpoint (which I already organised also acts funny. Nothing is aligned, nothing can be edited).
Please advise.