I had a similar problem with Pipex after it was bought out (forget by whom). I had left Pipex about a year before the sale but some 3-4 years after leaving I started received demands for arrears owing.
The problem is that unless their 'rogue' invoice is settled they pass it on to a debt collection agency and then things really go pear shaped.
practices should be outlawed !!
I say get the torches and pitchforks out....
Edited by risk_reversal (Fri 31-Aug-18 09:02:56)