More than three weeks after it was discovered thousands of pensioners and veterans had not received their winter energy payment entitlements the Minister has accepted responsibility for a series of mistakes.Social Development Minister Louise Upston's apology and acceptance that the buck stops with her comes a day after her ministry released a review, which found more than 30,000 benefits and other payments were wrongly suspended despite concerns raised for three months.It was August 18 when the initial winter energy payment mistake was first reported after an error in a bill was passed through all three stages under urgency.The winter energy payment should have been exempt from a law change that required main beneficiaries to confirm their circumstances annually to remain eligible.About 10 days later RNZ revealed a second error had occurred, this time affecting people's main benefits, after the same law change, rushed through under urgency, created a backlog of paperwork that ministry staff couldn't keep up with.According to the review the botch-ups affected more than 2400 main beneficiaries and some were left thousands of dollars out of pocket before they were backpaid, while the total arrears bill reached $2.5 million.MSD chief executive Debbie Power took responsibility for the costly mistake on Thursday, telling RNZ's Checkpoint the ministry hadn't done a good enough job, but she had no plans to resign.Upston had maintained she would front media when the review was released, but declined any interviews on Thursday.On Friday morning her office contacted RNZ at short notice to say the minister would be available shortly and had five minutes to answer questions.Speaking to RNZ she said the payment errors had been "incredibly frustrating and unacceptable"."I'm the minister. I accept responsibility."She said the review had not found the issue would have been avoided if the legislation had gone through a normal select committee process, rather than urgency."It was actually omitted significantly earlier in the policy development process."That's why the recommendations, I think, are really important in terms of greater quality assurance to ensure that policy, as drafted, actually reflects the government's intentions," Upston said."It was a mistake, it has been fixed, but I accept that that has meant that New Zealanders have gone without payments they were entitled to, and and I apologise for that."Upston told RNZ for those who missed their winter energy payments the issue was responded to urgently."Those that went without, it was repaid within 48 hours."She said her ministry should have been able to anticipate the backlog of paperwork issue as a result of the law change, which resulted in people missing out on their main benefits."They put more resources into it, but at that point, there were far too many people who had been without payments that shouldn't have had payments suspended."That's had an impact. I'm clear that the impact on some people was significant, and that's simply not good enough," she said.As to why Upston didn't front media on Thursday, as she said she would, Upston said it was important the ministry chief executive did so first."I think it was important for them to explain the review, explain what happened, and the recommendations, and as I said, it shouldn't have happened."What I want MSD to focus on now, that the initial challenges were fixed, is implementing the recommendations and to ensure they do better in future," she said.