Any gaming is impossible due to lag and it’s the worst at peak times. Must be congestion or absolutely awful traffic management, Fifa 20 just does not play at all how is should.
What package do you have? When I had Now TV broadband, I had no issues at all.
Are you playing Fifa via WiFi or Ethernet?
As I always find that devices work better when connected via Ethernet.
If you are on Fiber, then you should't be having too many problems. Sometimes unplugging the router for a few minutes and reconnecting works for me.
Worst case is you can get in touch with the broadband team on 0330 041 2460
If not I would then recommend using the Live chat.
1. NOW TV account & payments
2. Cancelling or renewing NOW TV Passes
3. Drop down 'How to get in touch'
4. Live Chat