Network is good but in game lags

It has been explained many times in the past that H2H lag is mostly outside EA's control. Think of your H2H game as a virtual path between you and your opponent that goes over EA servers.

Your Device -> your Internet Connection - > routing of your provider to EA servers local to you (e.g. London, UK) - EA servers over global cloud - Routing of your opponent to EA servers local to them (e.g. Sydney, Australia) < - opponents Internet connection <- opponents device. 

The only part that EA is responsible for is their servers and scaling them to the game's demands. Anything outside of it is the player's equipment/connection that EA has no control over (and never will).

The location of both players also matters, and the local to the player,  data centre hosting the EA servers. If you are in Europe and playing someone from Australia for argument's sake, then you will have an extremely lagged game as the latency between, e.g. London and Sydney will be 300+ ms. That's how networks and the internet work in layman's terms. So your connection could be great, but if your opponent's connection is rubbish or they are across the world, you both will have a laggy game.

There is no way around it until someone figures out how to use quantum entanglement for networks or Star Trek's subspace becomes real, heh. Anyway, the speed of light in fibreoptic networks is the limit, and we cannot cheat physics limitations, no matter how much people complain or blame EA.

Where the actual issues responsible for lagged H2H lie,  it is the matchmaking that matches players across the world for no real reason. Unless someone is fighting for the top 250, there is no need for them to have to play vs people on the other side of the world. Players should be matched up with people within their area (e.g. country or at most the continent). The devs are working on it, but keep in mind that they also need to try keeping the games within the same player tier and match you relatively quickly, so you don't wait for hours, so it is a balancing act.