There are 2 major reasons why you get the error:
Reason 1:
You installed the eSIM, but have not activated the eSIM yet. (Installation from a pop-up message)
You will now need to open the page to enter the "Access Code" again.
Situation ①
If you have selected to pick up the eSIM package at a counter, airport, or deliver it to your address...
Inside the package, there should be an A4 paper with a QR code for you to scan with your camera.
After you have scanned the A4 paper QR code, the page will ask you to enter the "Access code".
After you have entered the "Access Code", you will be able to click "Activate this eSIM"
Situation ②
If you have used the EKYC (online facial recognition) system for the ID check...
You should have received an email with an "eSIM issuance link".
EMAIL title: "Your order (Booking ID) is ready for eSIM issuance"
After you have scanned the A4 paper QR code, the page will ask you to enter the "Access code".
After you have entered the "Access Code", you will be able to click "Activate this eSIM"
Reason 2:
(for iPhone users only)
You downloaded the APN profile with an unstable internet connection; You have completed the above already, but the error still occurs.
In that case, please try the following steps:
1. Please turn off your other SIM cards/eSIMs. If it is a physical SIM card, please take it out of your phone.
2. Delete/Remove the Sakura Mobile APN profile.
(Go to Settings---> General---> VPN & Data Management---> Select Sakura Mobile profile---> Remove).
3. RESTART the phone/device.
4. After the restart, please reinstall the APN profile on your device.
***Please note that you MUST install the APN profile by using "Safari", not other browsers.
APN settings: https://www.sakuramobile.jp/apn-settings_longtermsimcard/
5. If the SIM/eSIM works, you can insert your physical home country SIM card and/or turn it back on.
6. If Steps 1-5 above do not work, please try deleting the current APN profile you have downloaded.
7. Get connected to a WiFi connection instead of your other SIM connection(s) - if applicable; please connect to a WiFi connection such as a home WiFi, public WiFi, etc.
8. Perform a Network Reset:
Old iOS version: Go to Settings---> General---> Reset---> Reset Network Settings
Latest iOS version: Go to Settings---> General---> Transfer or Reset iPhone---> Reset---> Reset Network Settings
※Please rest assured that a Network Reset will only erase APN settings, which can be reinstalled at any time.
This will not affect your SIM or any other data stored on your phone.
9. After the reset, please reinstall the APN profile on your device.
***Please note that you MUST install the APN profile by using "Safari", not other browsers.
APN settings: https://www.sakuramobile.jp/apn-settings_longtermsimcard/
(The link above is for monthly eSIMs as well.)
If the above does not resolve the issue, please contact us, as it may have been caused by other reasons.