Japan Airlines' website for reserving and purchasing air tickets has become almost inaccessible. The airline says access to the website surged amid a sales campaign.
JAL says the problem started late Wednesday, ahead of the campaign launch on Thursday.
It explains the disruption has made it impossible for customers to reserve or buy tickets for domestic and international flights in addition to the campaign tickets.
JAL says tickets for flights on and before April 11 can be purchased through its smartphone app.
Tickets for all dates can be booked or purchased via phone.
The airline says it has not confirmed any internal system failures or cyberattacks.
It adds that its airport systems have not been impacted, with check-in and flight operations functioning.
JAL says it is not clear when the problem will be resolved, and apologizes for the inconvenience.
It is calling on people to refrain from accessing the site as much as possible for now.