Tax credits DEA - after agreeing a Direct Debit??

StanStare

So I received a letter from the DWP stating that I owed around £650 from tax credits overpayment in 2003. My wife received the same letter. They stated that if I did not get in touch to arrange repayment they would issue a DEA to my employer.

We both telephoned them and separately arranged a monthly Direct Debit for an agreed amount - what an ordeal, I was on hold for nearly an hour before they answered! Over a week later I find that my employer has now been sent a DEA and as I work in finance, my job is now at risk!

How can I proceed? I guess I have no choice but to spend hours on the phone to them again, but will they cancel the DEA as we have an agreement or do they usually behave this way?