A programme that aims to get people to exercise by giving them free credits to book venues like tennis or badminton courts has hit a wall, as many found it hard to book facilities.
Dozens of sports enthusiasts have complained that they could not carry out the bookings under the ActiveSG scheme, which uses a smartphone application.
Mr Vincent Caldeira, who said he spent an hour trying to book a tennis court, called the new system "a mess".
"I get error messages all over the place, including "Oops! Looks like there has been a hiccup, check back in a bit!" when I try to pay! This is a real disgrace for all sports enthusiasts," he wrote on the ActiveSG Facebook page.
Mr Matthew Phang, 36, a health-care worker, was also unable to book a badminton court last week.
Others who had seemingly secured their bookings after multiple attempts were left fuming when their receipts showed the wrong time slots.
In an e-mail reply to The Straits Times, Mr Lai Chin Kwang, chief of ActiveSG, Sport Singapore, said public response has been overwhelming and acknowledged "there are processes that can be improved". He added: "We seek the public's patience and understanding while we mitigate these issues."
Launched on April 26 by then Acting Minister for Culture, Community and Youth Lawrence Wong, the ActiveSG scheme promised citizens and permanent residents free membership and credits of $100 to pay for entry to swimming pools and gyms and other sports activities.
In less than three weeks, more than 258,000 people have signed up for its free membership, Mr Lai revealed.
This meant it has exceeded its target of attracting up to 250,000 sign-ups.
Mr Lai said more than 100,000 individual bookings have been made over the last two weeks through the new ActiveSG system, a fourfold increase over the previous Web-based ICanBook booking system.
But the robust response has also apparently led to an overloading of the new app system.
Ms Lilian Koh, 49, chairman of iAPPS whose company created the mobile app, said the problems resulted from the volume of membership sign-ups and bookings of facilities. "But we have since solved the problems and the app is running smoothly now," she added.
The Straits Times booked a tennis court through the app last night smoothly, but understands that complaints about the app are still being received.
Others also aired unhappiness over how foreigners who signed up were also given credits.
Ms Koh said: "Those are isolated cases and the problems have already been addressed. We have also recovered the credits."
She added that her company has set up a service recovery team to help users who have encountered problems.
The public can send suggestions and queries to firstname.lastname@example.org or call the hotline on 6594-1388, Monday to Sunday, from 7am to 10pm.