Translation:Tim is interested in basketball, and Anna in volleyball.
I wrote "IN VOLLEYBALL " and it was not accepted because it should be "INTO". What?
Looks like "is into" was entered incorrectly (and "in" was missed out completely). Your answer should work now.
I got en error when I wrote "Tim is interested in basketball, and Anna is interested in volleyball"
Duolingo suggested "Tim into basketball, and Anna into volleyball," to me as a correct solution... This is not a real sentence in English! The translation "Tim is interested in basketball, and Anna - in volleyball," that is suggested on this page, is an improvement, but the dash (-) shouldn't be there. You can either leave out the dash, or replace it with "is interested".
They wanted me to write "and Anna - in volleyball" which is not an acceptable use of a dash in English.
tim is interested in basketball but anna in volleyball - rejected, "correct" answer - Tim is interested in basketball, but Anna into volleyball. Pretty sure this would not be worded this way very often.