"there is no connection" should be accepted
Connection = σύνδεση. Σχέση = relation or relationship
Check here where there are 8 dictionaries showing "σχέση" meaning among other things "connection".
any should be allowed
When doing translations for a learning course it's always best to stick as close to the original as possible. There is no mention of "any" (κανένας, καθόλου etc) in the Greek
Can you please add "No relationship exists" as an accepted translation?
Thank you, it has been added.
" There isn't any relationship" is one of the duolingo translations. And it sounds quite natural in English. "isn't any" is more emphatically negative,
than there "isn't a "
Please see the post just above yours which explains why "any" is not part of this translation. We always appreciate input from the community it has enhanced the course.
Can l use this sentence to prevent the other side of a dialogue from injecting a non relevant subject matter into a conversation?
In that case δεν έχει σχέση=It has no relationship, is better.