Since you specified a platform for the gem, you also need to specify it when yanking:
$ gem yank v2gpti -v0.2 --platform universal-darwin-13
Pregunta
I'm trying to replace a bad version of my gem on rubygems.com, but yanking fails. You can see at https://rubygems.org/gems/v2gpti that the gem does exist at v0.2. Why is this yank failing?
~ $ sudo gem yank v2gpti -v0.2
Yanking gem from https://rubygems.org...
The version 0.2 does not exist.
~ $
Solución
Since you specified a platform for the gem, you also need to specify it when yanking:
$ gem yank v2gpti -v0.2 --platform universal-darwin-13