diff --git a/www/manager6/storage/LvmThinEdit.js b/www/manager6/storage/LvmThinEdit.js
index c3b55d87d..63f1fd78f 100644
--- a/www/manager6/storage/LvmThinEdit.js
+++ b/www/manager6/storage/LvmThinEdit.js
@@ -148,7 +148,7 @@ Ext.define('PVE.storage.LvmThinInputPanel', {
 		    },
 		    change: function(f, value) {
 			let vgField = this.up('inputpanel').lookup('thinPoolSelector');
-			if (vgField) {
+			if (vgField && !f.isDisabled()) {
 			    vgField.setDisabled(!value);
 			    vgField.setVG(value);
 			    vgField.setValue('');