Slider 'Greying out' when I add a container

Hello. On the first slide there is a container containing a Title block (as yet not properly styled). When I try to add another container or indeed copy this one it greys out? I’ve tried twice with the same result. Can anyone see where I have made an error please? Thank you.


Here is my site Read-Only: https://preview.webflow.com/preview/sjflowers?preview=ca43ddc0eee63591b30341b6a7c0b6b2
(how to share your site Read-Only link)