When you deactivate a campaign variation in the traffic allocation step, meaning that you set the traffic to 0%, you might still see this variation online or see data coming through the reporting for this variation.
Note that modulation changes on a live campaign apply to new visitors only (those who see the campaign for the first time). A visitor who sees a variation always sees the same variation during their current and following sessions. As the allocation information is stored in the cookies, variations that are deactivated from the traffic allocation step are still visible for returning visitors.
If you have previously been assigned to the variation in question and want to make sure it is deactivated (not visible anymore), you must delete your cookies or open a new incognito window (with all other windows closed) in order to be considered a new visitor.
However, we don’t recommend changing the traffic allocation of a live campaign. If you want to do so, you should pause the current campaign and duplicate it with the desired traffic allocation.