Terrible lag since December 25

Ever since December 25 I have not been able to play a game of division rivals without there being terrible lag . I have fiber optic dsl with att and ran all diagnostics and my internet signal and ping is great it seems to be a problem with the game . All squad battles play smoothly. It’s gotten so frustrating that I want to quit the game all together. Can you please help

before December 25 the game was playing fine with no lag or glitches