ERA User Guide

Two-factor authentication (2FA)

Keep the device time correct for 2FA codes

You will haveThe ERA clock is set from the app, and your 2FA codes are accepted again.
Time3 min
You needERA device, ERA companion app on a phone with NFC

Authenticator codes are calculated from the current time, so ERA and the website must agree on the time to within a few seconds. ERA has no network and no time signal of its own: the clock is set only by the app, over NFC.

When you need this

  • ERA shows The device clock is not set, so TOTP codes do not work. when you open the 2FA list (a new device, or one whose battery was fully drained — the clock keeps running while ERA is switched off, but not without battery power).

  • A website rejects code after code, although you enter them in time.

  • ERA shows The device clock has not been synced for a long time, so TOTP codes may be wrong. — it raises this itself once it estimates the clock could be more than 15 seconds off. Until the app has calibrated the clock (syncs spread over at least two days) that can happen within about a day; afterwards only after months.

Steps

  1. On the Home screen, tap 2FA. If the clock is not set, a reminder appears over the list.

    Reminder over the 2FA list: The device clock is not set, so TOTP codes do not work, with UPDATE and SKIP
    Reminder over the 2FA list: The device clock is not set, so TOTP codes do not work, with UPDATE and SKIP

  2. Tap UPDATE. ERA shows the DEVICE TIME page and listens for the phone for 30 seconds.

    DEVICE TIME page with four numbered steps and a phone held to the device
    DEVICE TIME page with four numbered steps and a phone held to the device

  3. On the phone, open the app.

  4. In the app, tap Settings > Update device time. Any other NFC session (a firmware update, a Tap Sign transaction) sets the clock too.

    9:41
    Settings page of the app: General section, then Device settings with Update wallet, Authenticity Check, Verify app and Update device time.
    Phone: Settings, with Update device time under Device settings.

  5. The app shows Hold the wallet to the phone.

    9:41
    Bottom sheet over Settings: Hold the wallet to the phone — Unlock your ERA wallet and hold it flat against the back of the phone, with a spinner.
    Phone: Hold the wallet to the phone.

  6. Hold the phone flat against the back of ERA, as shown on the page. Keep it there until the page closes.

    ERA lying on the upper part of the phone screen while the app shows its NFC page.
    Photo: ERA resting on the phone for an NFC exchange (shown here during a firmware download; the time update uses the same position). Keep the two still until the page closes.

  7. Read the list: the dashes are replaced by live codes.

    2FA TOTP list with four accounts showing live codes and countdown rings
    2FA TOTP list with four accounts showing live codes and countdown rings

Done

The 2FA list shows six-digit codes with a countdown ring, and the website accepts them.

Note: Your time zone does not matter for the codes; only the exact moment counts, and the app sends it. Every NFC session with the app (a firmware update, an NFC signing tap) refreshes the clock as well. [VERIFY]

Trouble?

  • The DEVICE TIME page closed by itself → nothing arrived within 30 seconds. Tap UPDATE again and hold the phone to ERA only after the page is open.

  • You tapped SKIP → the list shows dashes instead of codes, and the account card shows an empty bar. Open the list again to get the reminder back.

    2FA TOTP list showing dashes instead of codes because the clock is not set
    2FA TOTP list showing dashes instead of codes because the clock is not set

  • Codes show, but the website still rejects them → the clock is set but drifted. Update the time again; then wait for the ring to restart and enter a fresh code. Most sites accept a code from the neighbouring 30-second window, but not further. [VERIFY]

  • The phone does not connect → make sure NFC is on in the phone settings and remove a thick case.