I had the same thing happen with my CB strat item. I needed to close the app completely and go back into the game. My offensive one had no trouble either.
If you go into your binder you can add that way, or in the lineup I have to use the left trigger to toggle the ovr/ new option to make them show that way also.
I got a WR one which it added and then have a mlb one and it won’t add it to lineup