diff --git a/Classes/LinphoneManager.m b/Classes/LinphoneManager.m
index e2b50a393..9bfd5520a 100644
--- a/Classes/LinphoneManager.m
+++ b/Classes/LinphoneManager.m
@@ -720,8 +720,8 @@ static void linphone_iphone_popup_password_request(LinphoneCore *lc, LinphoneAut
 	// let the wizard handle its own errors
 	if ([PhoneMainView.instance currentView] != AssistantView.compositeViewDescription) {
 		const char * realmC = linphone_auth_info_get_realm(auth_info);
-		const char * usernameC = linphone_auth_info_get_username(auth_info);
-		const char * domainC = linphone_auth_info_get_domain(auth_info);
+		const char * usernameC = linphone_auth_info_get_username(auth_info) ? : "";
+		const char * domainC = linphone_auth_info_get_domain(auth_info) ? : "";
 		static UIAlertController *alertView = nil;
 
 		// avoid having multiple popups