Thursday September 28, 2023

Issue summary:
On September 28, 2023 from approximately 11:54 AM PDT to 3:15 PM PDT, some Slack users experienced trouble receiving two-factor authentication (2FA) codes and therefore were unable to sign into Slack.

We determined this was caused by an upstream 2FA provider issue impacting code deliveries to US-based AT&T and Verizon devices. We monitored communications from the provider and confirmed Slack users could successfully sign in once the upstream issue was resolved.

3:55 PM PST

Our upstream provider is reporting that the issue is now resolved. Users should now be able to receive 2FA codes on US-based AT&T and Verizon devices as expected.

Thank you again for your patience, and we apologize for the disruption.

3:42 PM PST

Our upstream provider is reporting some signs of recovery. We will provide another update once we have more details to share.

We appreciate your patience while we sorted this out.

2:20 PM PST

We're actively investigating this issue and will be back with another update as soon as we have more information to share.

1:36 PM PST

Our 2FA upstream provider is currently experiencing issues, which prevents Slack native 2FA code from arriving to US-based AT&T and Verizon devices.

We’re on the case and will provide another update once we have more details to share. We’re sorry for the disruption.

1:05 PM PST