diff --git a/src/vim9compile.c b/src/vim9compile.c
index a8d8c7d..16898e3 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -1611,8 +1611,8 @@
     {
 	char *msg = (m->ocm_access == VIM_ACCESS_PRIVATE)
 				? e_cannot_access_private_member_str
-				: e_cannot_change_readonly_variable_str;
-	semsg(_(msg), m->ocm_name);
+				: e_member_is_not_writable_str;
+	semsg(_(msg), m->ocm_name, cl->class_name);
 	return FALSE;
     }