diff --git a/src/main/java/org/openstreetmap/josm/plugins/mapwithai/tools/MapPaintUtils.java b/src/main/java/org/openstreetmap/josm/plugins/mapwithai/tools/MapPaintUtils.java
index 2a80e5ca..439569eb 100644
--- a/src/main/java/org/openstreetmap/josm/plugins/mapwithai/tools/MapPaintUtils.java
+++ b/src/main/java/org/openstreetmap/josm/plugins/mapwithai/tools/MapPaintUtils.java
@@ -160,6 +160,7 @@ public static synchronized void addSourcesToPaintStyle(DataSet ds) {
             return;
         }
         List<String> sources = ds.allPrimitives().stream().map(MapPaintUtils::getSourceValue).filter(Objects::nonNull)
+                .map(s -> s.replace('.', '_'))
                 .distinct().collect(Collectors.toList());
         if (!styleSource.isLoaded()) {
             styleSource.loadStyleSource();