The challenging marker was adding the marks given to me for my correct answers to the other player!!!!...

Question

How that could happen???

is that a good question?
or the big numbers of users joined Solo Learn recently caused such mal functioning?

Answer 1

It probably was a bug.
You can report this in the Feedback Tab, in your Profile, the Options Symbol...
You get it.
:)

Answer 2

thanks but their event recorder may be unable to challenge that as such bugs are possibly doing their jobs before the answers reaching their destination servers,,,, Thanks for your advice..that What I have to do....but please change that scary nickname you are using for your profile...