I believe that they have to write to you giving notice, if they are planning a doorstep visit. You then can refuse them permission to do so and ask for all communications to be in writing only. The person that visited could be a sc*m artist, who is looking to obtain money from you that is not legally due. If there is a debt that has not be paid for a period of 6 years, then it will be statute barred, so not enforceable in court and only at your discretion whether you pay it or not.
Suggest that you ask for proof of the debt, by sending the debt company a letter. This is the sort of letter to send. They have to come back with proof of the debt, which should really be a statement of account from Barclays and ideally a copy of an assignment notice confirming that they can collect the debt.
You have contacted me regarding an account which you claim is owed.
I would point out that I have no knowledge of any such debt being owed to Barclays.
I am familiar with the CPUTR 2008 and the Office of Fair Trading's Guidance on debt collection, which states that it unfair to send demands for payment to an individual when it is uncertain that they are the debtor in question.
I would also point out that the OFT say under the Guidance that it is unfair to pursue third parties for payment when they are not liable. AND 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 account 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 Trading Standards and also inform the Office Of Fair Trading of your actions.
I look forward to your reply.