任何想法，为什么我可能会得到下面的错误时，启动一个MKLocalSearch？我到处都找过了，似乎找不到任何关于这方面的信息。
打印的错误是（来自guard let）：搜索企业失败：错误域=MKErrorDomain Code=2“（null）”UserInfo={MKErrorGEOError=-7}

let searchSpan = MKCoordinateSpan(latitudeDelta: 0.000018011, longitudeDelta: 0.000018011)
        let searchRegion = MKCoordinateRegion(center: location, span: searchSpan)

        let searchRequest = MKLocalSearch.Request()
        searchRequest.region = searchRegion
        searchRequest.resultTypes = .pointOfInterest
        searchRequest.naturalLanguageQuery = "bar"

        let search = MKLocalSearch(request: searchRequest)

        search.start { response, error in
            guard let mapItems = response?.mapItems else {
                print("Failed searching for businesses: ", error!)
                return
            }