Work through these checks in order. Do not delete the eSIM while troubleshooting.
1. Find the installed eSIM
Open Settings > Mobile/Cellular and check the complete eSIM list.
The eSIM name is not necessarily BambooSIM. Japan eSIMs may appear as KDDI or au. If a QR code cannot be used after an earlier installation attempt, or you saw an Unable to Activate eSIM message, the eSIM is likely already installed. The newest eSIM is usually near the bottom of the list.
2. Select it for data
- Turn the eSIM on.
- Select it under Mobile Data or Cellular Data.
- Temporarily turn off other SIMs/eSIMs.
- Keep network selection on Automatic.
3. Apply the correct settings
Check the exact product name in your confirmation email or account.
- Legacy eSIM whose instructions specify
globaldata: turn Data Roaming on and use APNglobaldatawhere the device provides an editable APN field. - Viettel, MobiFone, Japan KDDI, South Korea SKT Unlimited, and Australia Vodafone: keep APN on Automatic. Data Roaming is not required, although leaving it on is harmless.
- All other travel eSIMs: turn Data Roaming on and keep APN on Automatic.
4. Refresh the connection
- Turn Aeroplane Mode on for around 10 seconds, then off.
- Wait up to a minute for the network to reconnect.
- Restart the iPhone if needed.
For Japan KDDI products, only try the manual Japan Unlimited APN settings after every check above.
If the issue continues, please submit a ticket with your product name, iPhone model, current country, and screenshots of the Mobile/Cellular settings.