Withholding of information relevant to an appeal

Dear Department for Work and Pensions,
After serving the department with a subject access request they
have failed to supply all the information they hold. I specifically
asked for copies of the telephone conversations I had with them
which demonstrated their negligence and deliberate obstruction of
providing information I required to formulate an appeal I was
undertaking. None of these were provided only their edited and
altered transcript of one conversation. There were at least 7 in
the recent past and demonstrated their deliberate withholding of
said information. There was a wealth of medical information that I
had sent to them which they will not inform if it is on their data
base or not. Can you investigate this matter with some urgency
please.

Yours faithfully,
R.Scrivens