Upload shiny based flexdashboard


My issue is that I created a felxdashboard document, but it runs shiny. The problem comes when I want upload it to shinyapps.io. At the upload window (as it should work), I cannot find it, RStudio still sees the document as a static one, and tries to upload to Rpubs. Do you know how to upload it to shinyapps, since it runs shiny?
Thank in advance,