diff --git a/blueman/main/DBusProxies.py b/blueman/main/DBusProxies.py
index 27524620b..6f509d335 100644
--- a/blueman/main/DBusProxies.py
+++ b/blueman/main/DBusProxies.py
@@ -32,7 +32,6 @@ def __init__(self, name: str, interface_name: str, object_path: str = "/", syste
         except GLib.Error as e:
             raise DBusProxyFailed(e.message)
 
-
 class Mechanism(ProxyBase):
     def __init__(self) -> None:
         super().__init__(name='org.blueman.Mechanism', interface_name='org.blueman.Mechanism',
@@ -52,22 +51,25 @@ def __init__(self) -> None:
                          flags=Gio.DBusProxyFlags.DO_NOT_AUTO_START_AT_CONSTRUCTION)
 
     def activate(self) -> None:
-        try:
-            param = GLib.Variant('(a{sv})', ({},))
-            self.call_sync("Activate", param, Gio.DBusCallFlags.NONE, -1, None)
-        except GLib.Error:
-            # This can different errors, depending on the system configuration, typically:
-            # * org.freedesktop.DBus.Error.Spawn.ChildExited if dbus-daemon tries to launch the service itself.
-            # * org.freedesktop.DBus.Error.NoReply if the systemd integration is used.
-            logging.error("Call to %s failed", self.get_name(), exc_info=True)
-            Notification(
-                _("Failed to reach blueman-manager"),
-                _("It seems like blueman-manager could no get activated via D-Bus. "
-                  "A typical cause for this is a broken graphical setup in the D-Bus activation environment "
-                  "that can get resolved with a call to dbus-update-activation-environment, "
-                  "typically issued from xinitrc (respectively the Sway config or similar)."),
-                0,
-            ).show()
+        def call_finish(proxy: "ManagerService", resp: Gio.AsyncResult) -> None:
+            try:
+                proxy.call_finish(resp)
+            except GLib.Error:
+                # This can different errors, depending on the system configuration, typically:
+                # * org.freedesktop.DBus.Error.Spawn.ChildExited if dbus-daemon tries to launch the service itself.
+                # * org.freedesktop.DBus.Error.NoReply if the systemd integration is used.
+                logging.error("Call to %s failed", self.get_name(), exc_info=True)
+                Notification(
+                    _("Failed to reach blueman-manager"),
+                    _("It seems like blueman-manager could no get activated via D-Bus. "
+                      "A typical cause for this is a broken graphical setup in the D-Bus activation environment "
+                      "that can get resolved with a call to dbus-update-activation-environment, "
+                      "typically issued from xinitrc (respectively the Sway config or similar)."),
+                    0,
+                ).show()
+
+        param = GLib.Variant('(a{sv})', ({},))
+        self.call("Activate", param, Gio.DBusCallFlags.NONE, -1, None, call_finish)
 
     def _call_action(self, name: str) -> None:
         def call_finish(proxy: "ManagerService", resp: Gio.AsyncResult) -> None: