Old Address and Utility Bill affected my credit score

Orthodocs

Hello Forum,
My partner and I are applying for a mortgage, however we recently noticed her credit score had been reduced by over 600 points.
On further inspection it appears that her name remained associated with a Welsh Water account on a previous address. She was cohabitating at that time and her name was used by her then partner to establish a utility account. A tenancy termination was signed in January 2019 and it appears all bills were being paid by the then tenant until the most recent 2 bills.
We have contacted Experian who have said to contact Welsh Water. Welsh Water have said they will respond to the issue in the coming days and have 10 days to respond and a further 30 days from notification for the debt resolution team to respond.
Our issues are as follows:
1. Her name was used erroneously to establish an account therefore she did not know to cancel this at the time of vacating the address.
2. Welsh Water state that for Data Protection they cannot discuss this issue with me - understandable as I am not the supposed account holder - but neither is the current tenant of the last 2 years who continued living at this address.
3. The tenancy termination documentation has been submitted to Welsh Water as proof of leaving the property 23 months ago.

Where do we stand with regards this erroneous credit rating and association of bad debt with her file?
Many thanks for your advice.

FaceHead

1. The credit score is an irrelevant number.
2.An anomalous address (assuming the account is actually in good standing) is not going to cause a lender reject a mortgage application.
3. You should get it sorted anyway. If the real account holder who's using your partner's name stops paying Welsh Water will start chasing your partner for payment. Getting the account scrubbed off the credit record would be just treating one of the symptoms. Sorting it with Welsh Water is the right approach, and whilst 40 days is a long time it would probably take that long to get one or more credit records updated anyway.  You've submitted proof to them, so I would expect they will remove your partner from the account and update the credit record. 

[Deleted User]

You just need to dispute the debt and it will then be removed from her files.  

Fear not about her erroneous credit rating or her discarded 600 points. The points will never return, they are lost forever to the winds, but that doesn't matter as long as the information is corrected. If the information remains, then the focus needs to be on settling the debt.

7Phil

You'll need to wait out the supplier's complaints process and hope they can rectify the situation.
However, you/she aren't automatically entitled to relief because of a claim of her name being used in error. Even if a crime (fraud) was committed then you can't just allege it and expect the supplier to rectify immediately. She was living at the property where the water was being supplied at the time the account was set up? Sounds messy, so be realistic about the fact it'll take time to resolve.
I think that's where you stand, and in due course hope the bad debt can be lifted from her file.

I don't quite get what you mean about "A tenancy termination was signed in January 2019 and it appears all bills were being paid by the then tenant until the most recent 2 bills."
Do you mean the ex-partner continued to pay bills in her name after she left, or the previous two bills before they both left weren't being paid.