If you want to translate 'What is the meaning of your name?' into Spanish, you would say 'Cuál es el significado de tu nombre'? So when you translate back into English, you don't necessarily have to use the cognate 'significance', as 'meaning' would be the usual word. However, we would normally say, 'What does your name mean?'
This has been asked many times and (apparently) at one point Duo accepted it as a proper translation. If they are now rejecting it, I would say it's because it's a very different sentence structure. It's the difference between ¿Cuál es el significado de tu nombre? and ¿Qué significa tu nombre?
There are a lot of ways of saying/asking the same thing:
What does your name mean?
What is your name's meaning?
What is the meaning of your name?
How would someone describe the meaning behind your name?
If your name has a meaning, what is it?
What meaning is ascribed to your name?
One could argue that Duo should accept all of these possible translations, since they "mean the same thing." However, not all of them really match the original Spanish sentence very closely.
There is no difference in "meaning" between "What is the meaning of your name?" and "What does your name mean?". However, one uses the verb "mean" and the other uses the noun "meaning." Those are completely different parts of speech and require completely different constructions. If part of what Duo is drilling concerns sentence structure and parts of speech, then it makes sense for Duo to want us to match them as closely as practical.
Personally, I like learning different ways to say the same thing. To me, the goal is not to see if I can reduce one language to as few words and expressions as possible. Rather, I want to expand my knowledge and ability to use the language as flexibly as a native. Others want only to know that they can understand and be understood. There's absolutely nothing wrong with that. I just want a little more from Duo than basic comprehension.
The main definition of significance is "The quality of being worthy of attention; importance." so the translation could also be "What is the significance of your name."
When I read the Spanish sentence I pictured a person showing another person a list of qualities and asking them "Which is the significance of your name?" I was marked wrong. How do you translate "Which is the significance of your name? into Spanish?