Translation:Look at this problem as an opportunity!
If "opportunity" works in English in this context, then "chance" does too - they mean the same thing in this context. For example: "You have an opportunity to prove yourself" and "You have a chance to prove yourself" mean the same thing. And so do "Look at this problem as an opportunity [to improve your skills, to learn something new, etc.]" and "Look at this problem as an chance [to improve your skills, to learn something new, etc.]" The American Heritage, Collins and Random House dictionaries all define "opportunity" as "chance." There are some situations where one can be used but not the other, or where they have different meanings, but this is not one of them. Both "opportunity" and "chance" mean the same thing here (in English) and both should be accepted.
Good advice. I looked up "chance" in the Collins French English Dictionary. Here is what it says, complete with example sentences, for the definition of "chance" that applies to the sentence at issue here: " chance...(= occasion de réussir) donner sa chance à qn to give sb a chance la chance de sa vie the chance of a lifetime la dernière chance de qn sb’s last chance Rends-toi, Joe, c’est ta dernière chance ! Give yourself up Joe, it’s your last chance! de la dernière chance [conférence, négociations, réunion, épreuve, opération, manifestation] last-ditch tenter l’opération de la dernière chance to make a last-ditch attempt" Given what the dictionary says, why does Duo continue to insist that "opportunity" is a translation for "chance," but that "chance" is not a translation for "chance"? The dictionary quite clearly says Duo is wrong. If Duo is going to insist on picking nits, it should at least pick nits that actually exist.