Dear MikeMirzayanov:

The Polygon system is currently accessible, however, when starting working on a copy, it keeps displaying:

Oops! Something went wrong. Please try again later.

Also, you can try the following:

Return to the previous page
Back to home
Remove the current problem working copy
Oops! Something went wrong. Please try again later.

Also, you can try the following:

Return to the previous page
Back to home
Remove the current problem working copy

whether for existing working copy or new working copy.

Please fix it.