Deleting role broke my weekplan?

As the title says, I seem to have broken my Weekplan by deleting one of my roles (I deleted "Long term"). The same error appears both on my computer and my phone when I try to switch to the workspace "Work", refreshing sets me back to my "Personal" workspace. I'm not entirely sure that deleting a role is the reason, but it's basically the only thing I've done in the last few minutes.

whatsmybrowser.org/b/NYUL0RV