Housing New Zealand workers are being inundated with calls meaning long delays and thousands of unanswered calls.
The department closed a number of local offices in April, and set up a centralised national call centre, with the loss of up to 70 frontline jobs.
Public Service Association national secretary Brenda Pilott says staff workload has increased considerably since the number was set up.
"The other thing that's compounding things for them is the level of frustration and indeed anger that they're facing from people who in many cases have had to wait quite a long time to get through."
Ms Pilott says people are pretty irate when they do get through and time has to be spent calming them down.
