Blocking and switching stick

I don’t understand why my 85 plus online can’t block 3 rushers  and when I run the ball my line doesn’t hold blocks I promise I could hold a block longer against c jones then my oline in the game 

 pre snap I see cover 3 draw it a cover 3 beater opponent switching to every on defense there’s nothing to counter it when u have have time if rushing 3 cus blocking terrible