SINGAPORE

Amazon.com Inc’s entry into Southeast Asia has been marred by a delivery problem.

After introducing its Prime Now two-hour delivery service to Singapore on Thursday, the company now is unable to deliver goods to customers. As of Friday afternoon, its Prime Now app was telling users that “delivery is currently sold out. Check back soon.”

The service appeared to go down hours after its official launch on Thursday, according to media reports. “Due to great customer response, delivery windows are currently sold out,” Amazon spokeswoman Amanda Ip said, adding that the company is trying to resume normal delivery service.

Amazon kicked off in Singapore this week with its most aggressive service yet. Using the Prime Now app, customers there can get tens of thousands of items delivered to their door with free delivery on orders of more than S$40 ($29). The service is available as a free trial for a limited time in Singapore, before the company rolls out its Prime membership program.

The US e-commerce giant’s first venture into Southeast Asia could spark fierce competition with Alibaba Group Holding Ltd, which has acquired control of Lazada Group SA and is said to be considering an investment in Indonesia’s PT Tokopedia. The region of 620 million people is home to an e-commerce market forecast to reach $88 billion by 2025, according to a report by Google and Temasek Holdings Pte.