diff --git a/source/components/form/tree-select.mjs b/source/components/form/tree-select.mjs
index 24719372dd11709913e3e27fed753ad5a6814248..2a0ffb40f4749e3025689fa6800ca05b90c8c94c 100644
--- a/source/components/form/tree-select.mjs
+++ b/source/components/form/tree-select.mjs
@@ -288,6 +288,11 @@ function formatKeyLabel(node) {
  * @return {Array}
  */
 function buildTreeLabels(value) {
+
+	if (!this[internalNodesSymbol]) {
+		return [value];
+	}
+
 	let node = this[internalNodesSymbol].get(value);
 	if (node === undefined) {
 		node = this[internalNodesSymbol].get(parseInt(value));