No they cannot contact you at work without your permission. See your Telecomms department as they may be able to trace the number that called in, otherwise speak to British Telecom. As the law has been broken they may be able to trace it, but you would need to get the police involved too!(posted 7875 days ago)Also, no-one can call stating a lie, especially from the Inland Revenue!
A SCARN (SARN): Is a Subject Access Request Notice. It may be best to get someone independant from the debt to apply for this on your behalf (so not to acknowlegde the debt). You will need to write a letter of authorisation. They have 40 days to comply & can charge upto £10. These can be v useful!
The 6 year rule applies to lenders who have signed up to the Mortgage code (Council of Mortgage Lenders). Otherwise the 12yr rule may apply under the Limitation Act.