diff --git a/samples/Example.WebApp/Program.cs b/samples/Example.WebApp/Program.cs
index 6e4fe87..e127db8 100644
--- a/samples/Example.WebApp/Program.cs
+++ b/samples/Example.WebApp/Program.cs
@@ -1,7 +1,9 @@
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.IO;
 using System.Linq;
+using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore;
 using Microsoft.AspNetCore.Hosting;
@@ -14,6 +16,9 @@ public class Program
     {
         public static void Main(string[] args)
         {
+            // This is usually the case for production servers 
+            Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;
+            Thread.CurrentThread.CurrentUICulture = CultureInfo.InvariantCulture;
             CreateWebHostBuilder(args).Build().Run();
         }
 
diff --git a/src/I18Next.Net.Extensions/Builder/I18NextOptions.cs b/src/I18Next.Net.Extensions/Builder/I18NextOptions.cs
index 52bd1a9..a5510e6 100644
--- a/src/I18Next.Net.Extensions/Builder/I18NextOptions.cs
+++ b/src/I18Next.Net.Extensions/Builder/I18NextOptions.cs
@@ -7,7 +7,7 @@ public class I18NextOptions
         public string DefaultLanguage { get; set; } = "en-US";
 
         public string DefaultNamespace { get; set; } = "translation";
-        public IList<string> FallbackLanguages { get; set; }
+        public IList<string> FallbackLanguages { get; set; } = new List<string>();
 
         public bool DetectLanguageOnEachTranslation { get; set; }
     }
diff --git a/src/I18Next.Net/Plugins/ThreadLanguageDetector.cs b/src/I18Next.Net/Plugins/ThreadLanguageDetector.cs
index f875328..e4cca5c 100644
--- a/src/I18Next.Net/Plugins/ThreadLanguageDetector.cs
+++ b/src/I18Next.Net/Plugins/ThreadLanguageDetector.cs
@@ -18,7 +18,12 @@ public ThreadLanguageDetector(string fallbackLanguage)
 
         public string GetLanguage()
         {
-            return Thread.CurrentThread.CurrentCulture.IetfLanguageTag;
+            var languageTag = Thread.CurrentThread.CurrentCulture.IetfLanguageTag;
+            if (string.IsNullOrEmpty(languageTag))
+            {
+                return FallbackLanguage;
+            }
+            return languageTag;
         }
     }
 }