Publishing in play store

Hi everyone!! I can’t publish my application in play store, I followed the ionic guide to sign my application but I always get the following message when trying to load my application (Upload failed You uploaded an unsigned APK. You need to create a signed APK.).
Thank you

Did you sign the apk?

Which steps exactly did you follow?

i follow this guide from http://ionicframework.com/docs/v1/guide/publishing.html

Did you see any errors when running that? You need to make sure all steps complete with no errors in order to properly sign the app.