Is this the place? https://asterhouse.com/contact-us/
They show an email for 'contact'
Making a reservation is a bit more complex, but can be done by phone.
Making a Reservation
To proceed with making a reservation, please provide a valid credit card details i.e. name on card, card number, the expiry date, the 3 or 4 digit code on the back or the front of the card. To comply with UK regulations on data protection, please do not send your card details via email.
Credit card details can be provided by fax to +44 20 7584 4925 and by phone to +44 20 7581 5888.*
Alternatively: Please provide us with your contact number and we would be delighted to call you at an agreed time during our reservation office hours, London time 0800-2200 daily, to obtain the necessary card details.