When Apple Pay launched in Japan, one of the features is that it allowed users to turn their phones into a Suica pass. For those unfamiliar, Suica is one of several transit card systems that is used in Japan. By turning your iPhone into a Suica pass, it means that users don’t need to worry about bring their card around as long as they have their phone.

It proved to be extremely popular where users rushed to sign up when it was launched, causing the system to overload. Unfortunately it looks like its problems have yet to come to an end because in a report from local blog Ata Distance (via AppleInsider), there appears to be an issue with the iPhone X in which a bug is causing Apple Pay problems which in turn affects the Suica.

Users are claiming that after they have upgraded to the iPhone X, they are noticing some compatibility problems with the Suica Express Transit, an NFC-enabled system operated by JR East. Customers are complaining of slow response times while others are claiming it is outright unusable.

It is unclear if this is a hardware or software problem, but some customers have gotten lucky by exchanging their phones for new ones. Others who weren’t as lucky were denied replacements and were instead told that they were holding their phones wrong. It is unclear if Apple is aware of the issue as Ata Distance claims to have been tracking the problem for months already.

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