Complaints code

1. How to complain

Phone	01908 737 500
WhatsApp	+44 753 693 9500
Email	hi@tisa.one, with "Complaint" in the subject
Post	Complaints, TISA, 9Eons Limited, Luminous House, 300 South Row, Milton Keynes, MK9 2FR
Hours	Monday to Friday, 09:30 to 17:00 (closed UK bank holidays). Email and post any time.

Please tell us your name, your account or phone number, what went wrong, and what you would like us to do. Someone can complain on your behalf, such as a family member, a friend or an advocate, if you agree. Complaining costs nothing apart from your normal call charges.

2. Help to complain

If you have a disability or need help to make a complaint, tell us and we will make reasonable adjustments, for example calling you back at a time that suits you, giving you more time, or writing to you in large print or another format. You can use Relay UK to call us by prefixing our number with 18001.

3. What happens next

1. We try to put it right straight away. Most complaints are settled on the first contact.
2. If we cannot, we confirm we have your complaint within 48 hours, give you a reference number and tell you what we will do next.
3. We keep you up to date at least every 10 working days, and tell you as soon as we have an answer.
4. If you are unhappy with our answer, ask for it to go to a manager. A manager who was not involved will review it and reply within 10 working days.
5. Our final answer: we write to you with what we found and what we will do. If you do not tell us within 28 days that you are still unhappy, we may treat your complaint as resolved. If we cannot agree, we send you a Deadlock Letter, which also tells you how to go to CISAS.

We keep a record of every complaint and what we did about it for at least 12 months, and use what we learn to improve our service.

4. Taking your complaint further: CISAS

If we have not resolved your complaint within 6 weeks of you first telling us, or we have sent you a Deadlock Letter (whichever is sooner), you can ask CISAS (the Communications and Internet Services Adjudication Scheme) to look at it. CISAS is independent, approved by Ofcom, and free for you to use. Its decision is binding on us if you accept it, but you do not have to accept it.

• Website: cedr.com/consumer/cisas
• Phone: 020 7520 3814 · Email: cisas@cedr.com
• Post: CISAS, CEDR, 100 St Paul's Churchyard, London, EC4M 8BU

CISAS deals with complaints from residential customers and from small businesses with 10 or fewer employees, including not for profit customers. You have 12 months to refer your complaint to CISAS, from the date of our Deadlock Letter or, if we have not sent one, from the end of the 6 weeks.

5. Reminding you of your rights

We tell you about your right to use CISAS in this code, in our terms, on your bills and invoices, and in our Deadlock Letters. We also remind customers on monthly plans and business contracts in writing once a year.

6. Other help

• Ofcom, the communications regulator, cannot deal with individual complaints but gives advice: ofcom.org.uk/complaints
• Concerns about your personal information: email our data protection officer at dpo@9eons.com, or see our privacy policy.
• Citizens Advice consumer helpline: 0808 223 1133.

Copies of this code are free, in print or another format: call us or write to us.

Last updated 19 October 2026. TISA is a trading name of 9Eons Limited, company number 06393882.