Carly Randle, 33, a single mother based in Port Macquarie, New South Wales, told news.com.au she bought a A$89 ($98) Groupon voucher for a salon hair treatment to use on holiday down south but was unable to get an appointment or a refund.
"I could never use the voucher when it suited me," Randle told news.com.au.
"They would always say that they were booked out and didn't have the timeslots for Groupon vouchers."
According to Randle, she never got to use the voucher and it expired about six months after she purchased it.
"I reported the issue to Groupon but no refund was given even though it was requested," she said. "It was a waste of money, time and effort."
In response to the claims, a Groupon spokesperson told news.com.au the company was "continually monitoring feedback".
Customer satisfaction is our number one priority at Groupon," the spokesperson said.
"We will always assist customers with any redemption or booking issues they have as best we can.
"To be able to do this, we need to be contacted prior to the voucher expiring.
"The expiry date is clearly marked on the voucher, and we urge customers to check and make note of this as validity periods can vary."
Out of 1273 online reviews about Groupon Australia on productreview.com.au, 673 rate the service as "terrible" — compared to 406 that rate the service as "excellent". And it's not the only site where the product has received scathing reviews.
"As a recipient of a Silverwater Resort Groupon present, I have been unable to book in a weekend stay since there are no weekends available, and hence the voucher has gone to waste," one user wrote.
"They would not take this into consideration when I rang either Groupon or Silverwater.
"The receiver is still expected to pay another A$100-200 on top which defeats the purpose of the present."
Another user was allegedly unable to get a refund after buying a voucher for Movie World that "wouldn't download".
"It was immediately escalated to the resolution team, however as they could not provide the voucher, I requested a refund," the buyer wrote in an online complaint.
"Customer service put me on hold for a week and then stated no refund available.
"Have sent to PayPal to request a refund given I haven't received the voucher. Have also lodged a complaint with ACCC."
According to Consumer Affairs Victoria, it is an offence for a trader to accept payment for products or services and not supply them within a reasonable period.
Several group buying websites — including Scoopon, Spreets, deals.com.au, Cudo, LivingSocial, and Groupon — operate in Australia.
"We receive inquiries and complaints about group buying, particularly in areas such as hair, beauty and personal care services, restaurants and cleaning services," according to Consumer Affairs Victoria's site.
"Common complaints include non-supply and incomplete supply of products or services, and difficulty in booking services and redeeming vouchers."
There has been a spike in online complaints about Groupon following the 2017 Christmas period.
A Queensland woman, who didn't want her name published, was given a A$99 voucher for dinner at a Gold Coast restaurant as a Christmas gift, but said it went to waste.
"There were set dates on Groupon, it couldn't be used over the Christmas period, but every time I tried to book online for the available dates I was told it was booked out," she told news.com.au.
"Then the voucher expired.
"When I contacted Groupon I was directed to the merchant who then said they could only deal with the person who purchased it but it was a present so I didn't want to bother the person who gave it to me or make a fuss ... so the whole thing went to waste."
Groupon Australia didn't respond to questions from news.com.au.
The company's mission "is to become the world's biggest online marketplace", according to the Groupon Australia website.
"Since launching in major Australian and New Zealand cities in 2011, Groupon has worked with more than 9500 merchants and built a current customer base of 3.65 million subscribers who have purchased more than 8.6 million vouchers," it reads.
The Fair Trading Complaints Register provides information about businesses that are the subject of 10 or more complaints to Fair Trading in a calendar month.
A NSW Fair Trading spokesperson told news.com.au that Groupon had appeared on the Complaints Register "a total of four times since July 2016". It received 11 complaints in July last year and a further 17 complaints in November.
A QLD Office of Fair Trading said the department "does not generally confirm receipt of complaints against specific traders, as complaints alone do not constitute proven breaches of legislation".
"The OFT encourages consumers to read the terms and conditions of any deal offered carefully before purchasing a voucher through group buying, to make sure they fully understand them, especially in relation to cancellations," a statement from OFT to news.com.au read.
"Consumers should also make inquiries as to whether the deal purchased will be honoured at a time that suits the consumer."
A Consumer Affairs Victoria spokesman told news.com.au the department "doesn't confirm the existence of or comment on investigations relating to individuals or businesses as per our media code of conduct".
News.com.au has also contacted Choice, Australia's leading consumer advocacy group, for comment.