SINGAPORE - Customers who pre-bought tickets to the Alive Museum were left scratching their heads after the attraction closed this month, and gave no date for its reopening.

On Dec 20, the museum posted a notice of its temporary closure on its Facebook page.

"Alive Museum Singapore at Suntec City is temporarily closed. Further details on the re-opening will be provided shortly. We apologise for any inconvenience caused," it said.

The Alive Museum website displayed a white screen with the same message when The Straits Times checked on Thursday (Dec 29).

On Dec 22, there was another notice on Facebook saying that further details on the reopening will be posted on Dec 28.

It asked customers with pre-purchased tickets to send refund requests to ams.sales@adval.com.sg.

Doctor Sanjay Srinivasan, 44, told The Straits Times he only found out about the closure when he visited the attraction on Dec 26 with his family and friends.

He had bought 10 tickets for the discounted price of $100 at a bazaar in late November, and they expire in March 2017.

"There are no details about refunds, suddenly they have vanished," he said.

He wrote to the e-mail provided but did not get any satisfactory reply.

One e-mail showed to The Straits Times said that the Alive Museum team was away for the long weekend.

A second reply from Alive Museum said they were closed due to "certain operational issues".

"We will provide details on the re-opening of Alive Museum Singapore as soon as practicable. We will also provide details on how the tickets will be handled as soon as practicable," it said.

Ms Nurhayati Natasha, 36, did not pre-purchase tickets but tried to visit Alive Museum twice last week - on Tuesday (Dec 20) and Wednesday.

She said the attraction was shuttered, even though the announcement on Facebook was posted only at 3.55pm on Tuesday.

She and other family members took leave for the outing, and her extended family, including seven children, were "very disappointed", she said.

There were complaints from a number of customers on Alive Museum's Facebook page. Some said that their tickets will be expiring by the end of December.

"I sent an email re refund. No reply except for out of office message..." said Facebook user Stella Chow in a comment posted on Dec 27.

"It's disappointing this had to happen at this season. I bought eight tickets and took leave to visit the museum," said another Facebook user Sk Tan on Dec 24.

The Alive Museum, which is run by Adval Brand Group, opened in 2014. Visitors can interact and take photos with trompe l'oeil artwork, as well as two-dimensional paintings that look like three-dimensional scenes and objects.