diff --git a/AuthDialog.cpp b/AuthDialog.cpp
--- a/AuthDialog.cpp
+++ b/AuthDialog.cpp
@@ -67,7 +67,12 @@
 
     setupUi(this);
 
-    connect(userCB, QOverload<int>::of(&QComboBox::currentIndexChanged),
+    connect(userCB,
+#if QT_VERSION <= QT_VERSION_CHECK(5, 15, 0)
+            QOverload<int, const QString&>::of(&QComboBox::currentIndexChanged),
+#else
+            QOverload<int>::of(&QComboBox::currentIndexChanged),
+#endif
             this, &AuthDialog::checkSelectedUser);
 
     connect(buttonBox, &QDialogButtonBox::accepted, this, &AuthDialog::okClicked);