Outlook Add-in displayReplyForm

I’m creating an Add-in/Add-on for Outlook Mobile. I want to create a “Reply With” plugin so I’m doing: Office.context.mailbox.item.displayReplyForm("Reply").

But I get the response that I don’t have enough permissions, this is my how my permission looks like on the manifest.xml:
<Permissions>ReadWriteMailbox</Permissions>
Should’t this permission be enough to make the reply?