diff --git a/core/service.go b/core/service.go
index a7b40a4..f625596 100644
--- a/core/service.go
+++ b/core/service.go
@@ -687,12 +687,14 @@ func (sh *serviceDescription) authorize(w http.ResponseWriter, r *http.Request)
 			w.WriteHeader(http.StatusInternalServerError)
 			return
 		}
-		delts := link["_ts"].(primitive.Timestamp)
-		if !delts.IsZero() {
-			// 삭제된 계정. 삭제 되었다고 알려주자
-			w.Header().Add("MG-ACCOUNT-DELETED", "TRUE")
-			w.WriteHeader(http.StatusUnauthorized)
-			return
+		if link["_ts"] != nil {
+			delts := link["_ts"].(primitive.Timestamp)
+			if !delts.IsZero() {
+				// 삭제된 계정. 삭제 되었다고 알려주자
+				w.Header().Add("MG-ACCOUNT-DELETED", "TRUE")
+				w.WriteHeader(http.StatusUnauthorized)
+				return
+			}
 		}
 
 		linkid := link["_id"].(primitive.ObjectID)