try another way to implement the data stucture

UserService.DatabaseLayer/Repositories/BaseRepository.cs

@@ -0,0 +1,13 @@
+using LinqToDB.Data;
+using UserService.DatabaseLayer.DataModels;
+
+namespace UserService.DatabaseLayer.Repositories
+{
+    public abstract class BaseRepository
+    {
+        protected BaseRepository()
+        {
+            DataConnection.DefaultSettings = new UserDbSettings();
+        }
+    }
+}