Hi @Jenoli,
Sorry to read you’ve been having trouble with the website.
As you’ve been unable to enter the serial number, I’d suggest using the ‘Spare Part Purchase Journey’ detailed in this article - How to: Order spare parts and accessories.
Alternatively, follow this link, Support | Cordless vacuum cleaners | Dyson selecting V8 from the on-screen options and selecting the variant type. Once you have, choose ‘Spare parts and accessories’ from the next screen and proceed through to purchase the correct part.
If you'd prefer, you're welcome to call the Dyson Helpline to speak with our experts directly. You can find their number in the ‘Contact us’ section of the above page.
Stuart