my friend plays on nintendo and I play on Xbox

@randomest Hi Randomest, Could you please make sure both players have Cross Platform enabled. Cross-play should automatically be turned on. but in some cases it may not be. follow these steps. Go to the lobby. Click the cogwheel (Game Menu) in the bottom right corner of the screen. Click Settings. Scroll down to Cross Platform Play. Click Enabled to turn it on.
If both players have this switched on, could i suggest the switch player attempts to add you via the switch. Alternatively if there's any method of linking his switch to an EA account.