North District district all pin code and postal code list Singhik Gor Rangrang Manul Lingdem Tingvong Chungthang SO Phamtam Penlong BO Phudong Kabi Men Rong Rong Namok Lower Dzongu Lingthem Ramthang Bojoghari Mangan SO Sangkalan Phensong Shipgyare Lachen Lachung Naga Lingdok BO Tingchim