Trying to update flatpak 0.8.9 to at least 1.1.8 - ppa repo not working with apt?

hi there,

I’m trying to install bottles from flatpak but it wont let me because I dont have the latest version. I’ve added the ppa, so apt can get latest from that. Is there any other way to install it? or to force apt to get package from specfic ppa?
I’m using Debian Jessie

#instructions to update flatpak version
sudo add-apt-repository ppa:alexlarsson/flatpak
sudo apt update
sudo apt install flatpak