Assembly Payments experienced a minor incident on August 31, 2025 affecting Cards Payins, lasting 3d 1h. The incident has been resolved; the full update timeline is below.
Affected components
Update timeline
- investigating Aug 31, 2025, 10:33 PM UTC
Zai Engineers have detected a recurrence of the upstream card payment issue experienced on Friday. While not all transactions are impacted, some errors may again be experienced when using the make_payment and charges endpoints. Our team is in contact with our upstream provider to prioritise resolution of this issue. We’ll continue to share updates as soon as more information is available. Thank you for bearing with us as we work through this recurrence.
- investigating Sep 01, 2025, 12:01 AM UTC
Our investigation shows the impact is less severe than the partial outage experienced on Friday, however is still causing failures to some transactions. We are in close contact with our provider who is actively investigating the problem.
- monitoring Sep 03, 2025, 01:13 AM UTC
Our investigation with our provider has confirmed this issue only affects payments using cards that were added to Zai’s system during the previous upstream outage on Friday 29 August. Cards added before or after the outage are unaffected and can be used to transact successfully. * As a workaround, if possible, impacted payers may re-add their card and retry their payment. * If re-adding the card is not possible, we are continuing to work with our provider to restore functionality for the affected cards. Given this workaround, we will close this incident, but a further update will be posted here once the permanent fix has been installed by our provider. If you're not already subscribed to receive updates, you may follow this incident for alerts. We apologise for this trailing impact from Friday's upstream incident.
- resolved Sep 03, 2025, 11:55 PM UTC
Our provider has released a fix for the issue affecting payment cards added to Zai's system during the outage window on Friday 29 August. Transactions on these cards should be successful going forward. We have not detected any further instances of the "HTTP 400" error since this fix was put in place, however if you continue to experience problems with card payments, please contact our Support team at [email protected]. We apologise again for the extended impact caused by our provider's prior incident.