Plugin does not work :-(

Can you be a bit more specific please?

Clicking in the back-end on “Jomress” an error is returned and the dashboard does not open.
Thanks

What is the error?

Properties already loaded are requested.
Also, error 510 is returned during plugin activation. You need to try again several times.
I use WordPress version 5.7, but errors are also returned with older versions.
Thanks

Resolved! I installed Wprdpress 5.7 again and managed to activate jomres.
Thanks