I bought a Canon EOS 80D along with the 430EXIII-RT speedlite but can't get them synced. When I hold the button to auto focus prior to shooting the flash shoots but then when I take the pic it doesn't shoot. Almost like it is providing fill flash. I have checked my settings for using the external flash (ETTL), enabled flash firing, flash sync speed in Av mode set to auto, 1st curtain sync. Lots of bells and whistles on this one that's new to me (upgrading from the 60D) so I am not sure what I need to look for. Any help would be appreciated.