Upgrade Credit Checks

[DMNLJ]

So I have been with Three around 8-9 years, always had a handset and the Unlimited plan.

I went to upgrade today and then failed the credit check. Seems odd with the length of time I have been with Three.

seems to be a lot of users in the same predicament and unsure why this process is now needed, resulting in a loss of customers 

[beachsea]

Same 

I've been with 3 for more than 12  years. Multiple lines & handsets for family members on my account. Easy pay them £200 a month. Never been credit checked, apart from the first contract, but I was declined recently.Bills are always paid and DD always settled .

Experian account shows a bill that is not paid to three however 3 bill department has confirmed all my bills are paid 

No explanation or justification.Worst company