Associate teams only on interactor success

app/controllers/tournaments_controller.rb

@@ -39,10 +39,10 @@ class TournamentsController < ApplicationController
     if group_stage
       params.require(:playoff_teams_amount)
       groups = organize_teams_in_groups(teams)
-      # associate provided teams with tournament
-      tournament.teams = groups.flatten
       # add groups to tournament
       result = AddGroupStageToTournamentAndSave.call(tournament: tournament, groups: groups)
+      # associate provided teams with tournament on success
+      tournament.teams = groups.flatten if result.success?
     else
       # convert teams parameter into Team objects
       teams = teams.map(&method(:find_or_create_team))