Change where a campaign runs

Adds or removes the locations a campaign targets. Ids must come from google_resolve_locations; the tool verifies every id against Google and refuses anything it cannot find, so a wrong number never becomes wrong targeting. Use when: the user has named the places and you have resolved them to ids. Do not use when: the user wants to exclude a place rather than stop targeting it — an exclusion is a different criterion, and removing a targeted location is not the same as excluding it. The preview lists the place names, not the ids. Removing every location a campaign targets would stop it serving anywhere, so the tool refuses that outright. Location changes take effect within minutes and can move spend sharply: a new country starts competing against the same daily budget. If you are unsure which account, campaign or period the user means, ask them — do not guess ids or dates.