Double shell lines on imprint part of cutter

Hi all,

I’ve only just started using cookiecad but when I slice an imprint cutter, the imprint part is given double shell lines - and when printed there are gaps between these shell lines. I’m slicing using the latest version of cura and can’t see how to fill the gaps.

Ideally I want the imprint lines to be single lines but I do not know how to do that.

Any help would be appreciated!

Screenshot of the lines below