Dep routes never open

Relatively new to the game and never post. However- so frustrated with deep balls that I am asking for help. I play with univ of Texas and have receivers with 98 speed. Even with blocking adjustments I have under 2 seconds to throw. (Somewhat life like- so I am ok with that). However. My receivers never separate. Even against shit teams with corners at 88 speed. They are always in lock step and if the ball is contested they usually pick it. Frustrating as go routes are a pick or sack. Help please.