Instead, they had to get the visa upon landing.

Yesterday, a family of three showed up at the Hong Kong airport for a flight to Taiwan for holiday but only the father got hold of an online visa. "It's harder than buying concert tickets," he said.

Taiwan resumed online visa application for individual visitors from Hong Kong and Macau at 9am yesterday.

As they had done prior to the island imposing travel restrictions in February 2020, Hongkongers logged onto the internet portal for entry permits in the morning.

But some travelers said they had trouble logging in. Tourist Ng, who was at the airport getting his travel documents ready, said: "The website has been down since 9am. I'll apply for the visa and pay the fee on arrival."

Processing a visa application on arrival comes with a fee of NT$300 (HK$77). But tourist Mok said: "I have not been there in more than three years. I'm visiting Taiwan to travel and see the sights,. It's the first day of reopening, so the system might not be able to process uploads. I expected this."

A Hong Kong visitor who had studied in Taiwan said he has not been able to visit teachers and classmates there since he graduated in 2019 due to pandemic restrictions.

He said he planned a trip for the first day of the reopening, adding that he had missed the food at the night markets in Taiwan.

Under Taiwan's "0+7"Covid measures, travelers will have to stay masked for up to eight days including the date of arrival, despite Taiwan lifting its indoor mask mandate yesterday.

Failure to follow those regulations will result in fines of up to NT$15,000.