Tren Dick, Deca Dick basically 19nor erectile dysfunction lol.
This usually happens when you are either not running high enough test, when you let your estrogen get out of control, you take too much AI to combat estrogen or your progesterone gets too high.
Long story short, get bloods and monitor your levels. Take just enough ancillaries to keep things in check and run your test the same or higher than your Deca and you should be fine.