Says £6 a month, yet offer was 5GB for £5 for 15 months?

Thanks for the replies.

I e-mailed [email protected] and they have since fixed this issue on my account: I've been refunded £1 for this-month, and all screens on the website and mobile-app do now show £5 a month going-forwards, not £6.

I'd suggest anyone who signed-up for the "5GB-for-£5-for-15-months" offer check they are actually getting it; if not, contact the team and ask: "so... can I actually get the offer I signed-up for?" 🙃