diff --git a/examples/device/webusb_serial/src/main.c b/examples/device/webusb_serial/src/main.c
index 838d86381..eaca78c73 100644
--- a/examples/device/webusb_serial/src/main.c
+++ b/examples/device/webusb_serial/src/main.c
@@ -112,7 +112,7 @@ void echo_all(uint8_t buf[], uint32_t count)
   if ( web_serial_connected )
   {
     tud_vendor_write(buf, count);
-    tud_vendor_flush();
+    tud_vendor_write_flush();
   }
 
   // echo to cdc
@@ -211,7 +211,7 @@ bool tud_vendor_control_xfer_cb(uint8_t rhport, uint8_t stage, tusb_control_requ
           blink_interval_ms = BLINK_ALWAYS_ON;
 
           tud_vendor_write_str("\r\nWebUSB interface connected\r\n");
-          tud_vendor_flush();
+          tud_vendor_write_flush();
         }else
         {
           blink_interval_ms = BLINK_MOUNTED;