SINGAPORE - What do you do when your passport is not stamped at immigration?

This was a running thought for a Singaporean couple who went to Malaysia last Friday (April 5) and realised something was amiss after they had passed through the Johor Baru checkpoint on the way back.

It led to them scrambling to cancel their next planned trip to Malaysia and search for a solution - they feared they would be detained upon re-entering the country because JB authorities had not stamped their passports.

But respite came after they sought advice from the Malaysian immigration authorities, who told housewife Tay Mui Hiang, 49, and her husband, technician Koh Meng Soon, 46, to head to the JB checkpoint to settle the matter.

The couple did so on Tuesday and the JB checkpoint authorities were able to rectify their passport records.

The Straits Times understands that for Singapore passports that are not stamped, the affected Singaporeans should get in touch with the Malaysian authorities as soon as they can to correct their exit records.

If in doubt, they can contact the Singapore Ministry of Foreign Affairs (MFA) for advice.

Should affected Singaporeans be detained, they can contact the Singapore High Commission in Kuala Lumpur or the Consulate-General in JB for consular assistance.

Concerns over being detained weighed heavily on Madam Tay and her husband after their incident.

They had entered JB around 11am on Friday and were returning to Singapore at about 1pm on the same day after lunch and having picked up Madam Tay's brother-in-law and some relatives, reported Chinese-language evening daily Shin Min Daily News on Sunday.

They were travelling as a group of six - three of them are Malaysians and the rest are Singaporeans, including Madam Tay and her husband.

After passing the JB checkpoint, Madam Tay said she knew that as travellers, they should check their passports and make sure that they were stamped. However, they did not want to hold up traffic to check their passports at the checkpoint because there was a long queue of cars behind them.

"Sometimes, they just stamp randomly and it could be on any page, so we have to look for it and it takes time," she said.

"When we realised that our passports were not stamped, we were already halfway across the Causeway."

Only she and her husband did not get the stamp. The third Singaporean in their group had his passport inked.

When they reached Singapore's Woodlands Checkpoint, they asked the customs officer for advice on what they should do.

"He told me it is normally not a problem and there was no need for us to make a U-turn and go back to the JB customs to get it stamped," Madam Tay told ST on Sunday.

They decided to pass through the checkpoint but started to worry when they got home because family and friends recounted unpleasant experiences of people whose passports were not stamped.

She said that her younger brother had a similar issue before, and when he tried to enter Malaysia after that, he was detained and questioned for about two or three hours.

She promptly cancelled a family trip to Genting after returning last Friday night. The trip was planned for Sunday to Thursday.

"If the Malaysia customs detain me on the way there, what do I do?" said Madam Tay, adding if she and her husband were to be detained, her elderly in-laws would be at a loss.

The cancellations cost the family about RM1,200 (S$396).

But the husband and wife managed to resolve the passport matter on Tuesday, ahead of another holiday in Kukup, Johor, that they planned to take in the coming weeks.

People who frequently travel between Singapore and Malaysia, especially via the land checkpoints, should ensure that their passports are presented to a Malaysian immigration officer and stamped correctly before leaving the Malaysian immigration booth, said Singapore's MFA in a Facebook post on March 15.

Failure to do so is an immigration offence in Malaysia and the penalties can be severe, including detention, a fine, and a ban from future entry into the country.