My wife was in your situation a couple of years ago- had a blemish free attendance record at work, was sick for a week and a few weeks later got a letter like yours. Basically if you are off work for more than 2 days in future you need to go to your doctor to have them sign a special cert, when you are ready to return to work they must sign a different cert. These documents are returned by you to the Dept. of Social Welfare. You can nominate payment of the disability benefit to yourself directly or to your employer- if they are paying you while out sick. I had ocassion to avail of this payment myself this year and like you I was new to all this. That said your employer is only trying to recover monies which you are entitled to through your PRSI contributions.