A post that appeared on Dr Vivian Balakrishnan's Facebook page early Thursday morning raised the public's concerns about a possible violation of the Cooling-off Day regulations, local media reported.
In the post, he talked about meeting "members of our Cashew family during campaigning."
Dr Balakrishnan, People's Action Party's (PAP) candidate for the Holland-Bukit Timah GRC, responded in a statement: "It has been brought to my attention that a Facebook post that was originally uploaded on Sept 4, has been auto-posting recurrently since then."
"Despite multiple attempts by the page administrators to stop this, the problem recurred at 1.52am on Sept 10."
Besides informing Facebook's headquarters of the bug, Dr Balakrishnan also requested for the page to be locked down "to prevent further postings".
According to Channel NewsAsia, Facebook is investigating the incident.
Meanwhile, the Elections Department (ELD) said in a statement that it noticed several election advertising posts on a few candidates' and parties' social media accounts.
People's Action Party, People's Power Party and Reform Party were among those ELD cited as examples.
The posts were taken down after the Assistant Returning Officer sent out reminders to the candidates.
Sept 10 was declared Cooling-off Day, a 24-hour campaign silence period to allow voters to rationally reflect on various issues raised at an election before going to the polls.
Candidates are prohibited from campaigning and election advertising on that day.
Singaporeans will cast their votes on Polling Day Sept 11.