It look like their UK service is unavailable - UK Helpline Unavailable 8/8/23 - Anyone know why?.

‘Working intermittently’ is a little vague to work on.. Is it switching on/off? Filter light showing? Does it only do it with a specific attachment? In each case, I’d head over to their help section online. I’m sure the answers there! https://www.dyson.com/support/

Hi @Amy davies, 

Doesn’t sound like a great experience, let’s see if I can help point you in the right direction. 

If you’re trying to contact our helpline in GB&I, this is currently unavailable due to circumstances beyond our control. More information on this can be read here - UK Helpline Unavailable 8/8/23 - Anyone know why? | Dyson Community.

In terms of getting you pointed in the right direction, @Eagles is right. Our ‘Support’ page hosts self-serviced diagnostics, which are designed to identify issues and recommend solutions, based on your input. This is a great place to start !

If this isn’t able to recommend a solution, you’ll be prompted to contact Dyson directly. The best way to do this is to reach out via our websites Live chat or on WhatsApp. To get started here simply click on our Guides and manuals link, navigate to the ‘Contact us’ section of the page and start a WhatsApp conversation.

Thanks, 

Stuart

Mine does the same thing but usually when I have the round brush on. I think it overheats. Although it’s not really working at all at the moment think loose wire. 
I have had it serviced but still does it.