diff --git a/packages/runtime-core/src/componentPublicInstance.ts b/packages/runtime-core/src/componentPublicInstance.ts
index 018187fc..03ee0e0e 100644
--- a/packages/runtime-core/src/componentPublicInstance.ts
+++ b/packages/runtime-core/src/componentPublicInstance.ts
@@ -458,7 +458,7 @@ export const PublicInstanceProxyHandlers: ProxyHandler<any> = {
   ) {
     if (descriptor.get != null) {
       // invalidate key cache of a getter based property #5417
-      target.$.accessCache[key] = 0
+      target._.accessCache![key] = 0
     } else if (hasOwn(descriptor, 'value')) {
       this.set!(target, key, descriptor.value, null)
     }