That's nearly as many as it had for the whole of the year to June 30 when it dealt with 28 cases.
The spike has been driven by people trying to nab a better deal on their mortgage rate in the wake of a steep fall in the interest rates.
Sladden said while most people understood they had to pay a fee to break the contract there was misunderstanding over how it was calculated.
"I think people are aware there is a cost associated with it. The miscommunication is how the break cost is calculated and how it can change over a short period of time."
Misunderstanding between banks and their customers is at the heart of a lot of the cases seen by the Banking Ombudsman scheme.
While she's never had a run-in with her own bank, Sladden said being misunderstood was something most people could relate to.
"I think we have all experienced being misunderstood. I have a high level of empathy for people that don't feel they have been heard. I think most lawyers have a strong sense of people having access to justice."
A born and bred Wellingtonian, Sladden originally trained as a lawyer and worked in private practice in Wellington and the public sector before moving overseas.
She completed a Masters in Public Health at Boston University and came back to New Zealand where she worked for the Health and Disability Commission.
Sladden says her interest in helping others resolve disputes stems from a passion for problem solving.
"I'm really interested in problem solving. I'm naturally curious.
"At the heart it is about dealing with people."
She says she has always wanted to make a positive difference.
While the health and disability and banking sectors might seem very different Sladden said the two had clear commonalities.
The people she dealt with at the Health and Disability Commission had suffered from a medically adverse event.
Those she helps through the banking ombudsman service may be facing financial hardship and that can also have negative implications for a person's health.
"I think coming into the banking ombudsman scheme and reviewing the range and number of complaints, I've been struck by the importance of people's financial security to people's well-being.
"[That's why] I really support the focus on building financial capability - the importance of people learning about the risks associated with certain products and making informed decisions."
One of Sladden's biggest challenges in the year ahead will be implementing a number of changes to the scheme after it went through an external review.
Sladden said the structure of the scheme would be modernised as well as the language used to describe complaints and disputes.
It has also proposed increasing the timeframe in which people can make complaints from two months to three months after a bank has made its position final and up to six months in exceptional circumstances.
Banks will also have to get consent from the ombudsman before they can take legal action against a customer who has lodged a complaint.
In the past the bank had to tell the ombudsman about the legal action but could still pursue it which meant the ombudsman then had to drop the case as it was no longer in its jurisdiction.
"It doesn't happen very often. But we think it is important to make it clear it is our role to try and resolve disputes with banks."
Banks will also be required to notify the ombudsman service if they are going to take debt recovery action against a customer where a complaint is being dealt with by the scheme.
The scheme will move to a principles-based approach to solving disputes rather than being so prescriptive.
At the moment every case must move through a process of being an inquiry to a complaint and then a dispute.
The service then issues an initial assessment before a formal decision is made.
"Often the process becomes unnecessarily protracted," says Sladden.
Instead she wants people to get answers much sooner.
At the moment most simple disputes are resolved within 40 working days while complex ones can take up to 200 days.
"Our aim is to provide a simple and speedy service.
"Bearing in mind it has to be underpinned by being fair," says Sladden.
• Nicola Sladden, Banking Ombudsman.
• Started new role on August 1.
• Age: mid-40s.
• Has been deputy Banking Ombudsman since 2011.
• Before that was chief legal counsel for the office of the Health and Disability Commissioner where she worked for 12 years.
• Has a Bachelor of Laws Degree from Victoria University and a Masters in Public Health from Boston University.
• Married with four teenage children.
• Enjoys tramping in her spare time.
