If you for some reason need to change one or more Campaign names in, for example, your AdWords account, you will likely want this to be reflected in your Funnel account.
Funnel does not do a daily download all historical data from the connections made in a Funnel account, it only does so the first time that connection is successfully made. So in order to make sure that any Campaign name changes you make are applied to all your Funnel data, a full re-download of the data from the affected connections is the safest way to go. Also note that a reconnect of your data source will not trigger a full re-download. Read more about what a reconnect do here.
As a user, you cannot trigger this yourself without removing and then adding you account all over again. Instead, contact us through Support and we will help you out.