Is this in the sense of "this is not my job"?
It is quite possible that's what this sentence means, although frankly, I would specify what exactly is not your role.
It's not my function?
This seems to be a rather unusual choice in contemporary language, as I was told...
Or even "This is not my place"
[though place would be something very different!]
Shouldn't there be something after "not my place", like "it's not my place to judge/decide/question..."?