"Are we playing?"
"We play" = Wij spelen.
You added a superfluous zijn to it in an attempt to make something like the English present continuous. Of course, even if Dutch had a present continuous formed exactly as in English, it would be wij zijn "speling".
The software thought you were going for the Dutch continuous construction wij zijn aan het spelen ("we are on the play") and thus gave you a correction based on that.