Hello,
I am a Confluence admin.
We are using Confluence Data Center 10.1.2 with Lucidchart plugin 2.2.3 (free plan).
We are having trouble with adding new diagrams on Confluence pages with Lucidchart macro. However our other diagrams are ok on other pages, still visible. When trying to add a new diagram, afer selecting the diagram, we have a loading page and then an error 504. Here are the screenshots :



I tried uninstall and reinstall, but the problem continues.
Thank you for your help !