Unknown O2 account chased by Lowell

[sarsons]

Hi,
So I recently looked at my online Lowell account after having a debt transferred to them and needing to know how much is left and found an unknown O2 account being chased by them.
I emailed them a proof of ownership letter see below for that letter,

I got an email back saying they will contact O2 and provide any proof they have.

So today I got a letter stating they have enclosed documents from O2 but all they've included is a transaction list no further information. See photo

On the cover letter it does say the account will remain on hold until they receive more information from the client

Any help with this to actually get proof I own the debt or get this removed off my credit file as I have no recollection of this account

Thanks
Sarsons

Dear Sir/Madam
Account No: "removed"
After registering online for an account to manage my talk talk debt with yourself ref " removed acc number", I noticed another account which you claim is owed by myself.
I would point out that I have no knowledge of any such debt being owed to O2 (UK) account ltd
I am familiar with the Consumer Credit sourcebook of the Financial Conduct Authority (FCA) which states the following rules.
"A firm must not ignore or disregard a customer's claim that a debt has been settled or is disputed and must not continue to make demands for payment without providing clear justification and/or evidence as to why the customer's claim is not valid." 7.5.3
"A firm must suspend any steps it takes or its agent takes in the recovery of a debt from a customer where the customer disputes the debt on valid grounds or what may be valid grounds." 7.14.1
"Where a customer disputes a debt on valid grounds or what may be valid grounds, the firm must investigate the dispute and provide details of the debt to the customer in a timely manner." 7.14.3
"Where there is a dispute as to the identity of the borrower or hirer or as to the amount of the debt, it is for the firm (and not the customer) to establish, as the case may be, that the customer is the correct person in relation to the debt or that the amount is the correct amount owed under the agreement." 7.14.4
"A firm must provide a customer with information on the outcome of its investigations into a debt which the customer disputed on valid grounds." 7.14.5
"Where a customer disputes a debt and the firm seeking to recover the debt is not the lender or the owner, the firm must:
(1) pass the information provided by the customer to the lender or the owner; or
(2) if the firm has authority from the lender or owner to investigate a dispute, it must notify the lender or owner of the outcome of the investigation." 7.14.6

In not ceasing collection activity whilst investigating a reasonably queried or disputed debt you are using deceptive/and or unfair methods.
Furthermore, ignoring and/or disregarding claims that debts have been settled or are disputed and continuing to make unjustified demands for payment amounts to physical/psychological harassment.
I would ask that no further contact be made concerning the above accounts unless you can provide evidence as to my liability for the debt in question.
I await your written confirmation that this matter is now closed. Otherwise I will have no option but to make a complaint to the trading standards department and consider informing the FCA of your actions.
If appropriate I will also take this matter forward as a complaint to the Financial Ombudsman Service and Information Commissioner's Office.
I look forward to hearing from you.
Yours faithfully

[sarsons]

After some more digging ive found out that as per companies House both O2 (UK) ltd and Telefónica were both dormant companies

Lowell are stating the balance is true and owing and aren't budging *♂️

Any help getting this sorted?