diff --git a/simple_audit/admin.py b/simple_audit/admin.py
index faf3902..ceca723 100644
--- a/simple_audit/admin.py
+++ b/simple_audit/admin.py
@@ -7,7 +7,7 @@
 from django.utils.html import escape
 from django.urls import reverse
 from django.shortcuts import redirect
-from django.conf.urls import url
+from django.urls import path
 from .models import Audit
 from .signal import MODEL_LIST
 
@@ -43,6 +43,7 @@ def queryset(self, request, queryset):
             return queryset
 
 
+@admin.register(Audit)
 class AuditAdmin(admin.ModelAdmin):
     search_fields = (
         "description",
@@ -62,8 +63,8 @@ class AuditAdmin(admin.ModelAdmin):
     def get_urls(self):
         urls = super(AuditAdmin, self).get_urls()
         my_urls = [
-            url(
-                r"^revert/(?P<audit_id>\d+)/$",
+            path(
+                "revert/<int:audit_id>/",
                 self.admin_site.admin_view(self.revert_change),
                 name="simple_audit_audit_revert",
             )
@@ -85,19 +86,25 @@ def revert_change(self, request, audit_id):
 
         return redirect("admin:simple_audit_audit_changelist")
 
+    @admin.display(
+        description=_("Date"),
+        ordering="date",
+    )
     def format_date(self, obj):
         return obj.date.strftime("%d/%m/%Y %H:%M")
 
-    format_date.short_description = _("Date")
-    format_date.admin_order_field = "date"
 
+    @admin.display(
+        description=_("Description")
+    )
     def audit_description(self, audit):
         desc = "<br/>".join(escape(audit.description or "").split("\n"))
         return desc
 
-    audit_description.allow_tags = True
-    audit_description.short_description = _("Description")
 
+    @admin.display(
+        description=_("Current Content")
+    )
     def audit_content(self, audit):
         obj_string = audit.obj_description or str(audit.content_object)
 
@@ -113,9 +120,11 @@ def audit_content(self, audit):
             }
         )
 
-    audit_content.short_description = _("Current Content")
-    audit_content.allow_tags = True
 
+    @admin.display(
+        description=_("User"),
+        ordering="audit_request__user",
+    )
     def audit_user(self, audit):
         if audit.audit_request:
             return u"<a title='%s' href='%s?user=%d'>%s</a>" % (
@@ -127,9 +136,6 @@ def audit_user(self, audit):
         else:
             return u"%s" % (_("unknown"))
 
-    audit_user.admin_order_field = "audit_request__user"
-    audit_user.short_description = _("User")
-    audit_user.allow_tags = True
 
     def queryset(self, request):
         request.GET = request.GET.copy()
@@ -143,4 +149,3 @@ def has_add_permission(self, request):
         return False
 
 
-admin.site.register(Audit, AuditAdmin)
diff --git a/simple_audit/middleware.py b/simple_audit/middleware.py
index 4fc61c6..27a58e7 100644
--- a/simple_audit/middleware.py
+++ b/simple_audit/middleware.py
@@ -11,7 +11,7 @@ class TrackingRequestOnThreadLocalMiddleware(MiddlewareMixin):
 
     def _get_ip(self, request):
         # get real ip
-        if "HTTP_X_FORWARDED_FOR" in request.META:
+        if "x-forwarded-for" in request.headers:
             ip = request.META["HTTP_X_FORWARDED_FOR"]
         elif "Client-IP" in request.META:
             ip = request.META["Client-IP"]
diff --git a/testproject/requirements.txt b/testproject/requirements.txt
index ad37206..48849df 100644
--- a/testproject/requirements.txt
+++ b/testproject/requirements.txt
@@ -1,2 +1,2 @@
-Django==3.2.10
-six==1.11.0
+Django==4.1.6
+six==1.16.0
diff --git a/testproject/settings.py b/testproject/settings.py
index 683c031..baaf062 100644
--- a/testproject/settings.py
+++ b/testproject/settings.py
@@ -46,7 +46,6 @@
 
 # If you set this to False, Django will not format dates, numbers and
 # calendars according to the current locale.
-USE_L10N = True
 
 # If you set this to False, Django will not use timezone-aware datetimes.
 USE_TZ = False
diff --git a/testproject/simple_app/admin.py b/testproject/simple_app/admin.py
index a8200fd..e7b94ed 100644
--- a/testproject/simple_app/admin.py
+++ b/testproject/simple_app/admin.py
@@ -3,29 +3,29 @@
 from django.contrib import admin
 
 
+@admin.register(Pizza)
 class PizzaAdmin(admin.ModelAdmin):
     list_display = ('name',)
     filter_horizontal = ('toppings',)
 
 
+@admin.register(Topping)
 class ToppingAdmin(admin.ModelAdmin):
     list_display = ('name',)
 
 
+@admin.register(Message)
 class MessageAdmin(admin.ModelAdmin):
     list_display = ('title', 'text')
 
 
+@admin.register(Owner)
 class OwnerAdmin(admin.ModelAdmin):
     list_display = ('name',)
 
 
+@admin.register(VirtualMachine)
 class VirtualMachineAdmin(admin.ModelAdmin):
     list_display = ('name', 'cpus', 'owner')
 
 
-admin.site.register(Message, MessageAdmin)
-admin.site.register(Owner, OwnerAdmin)
-admin.site.register(VirtualMachine, VirtualMachineAdmin)
-admin.site.register(Pizza, PizzaAdmin)
-admin.site.register(Topping, ToppingAdmin)