If you are using a ‘Japan Voice + Data SIM’ (previously known as the ‘Japan Unlimited SIM v2’ SIM) that was purchased after Oct 12th 2021, please visit the following link: v2 Troubleshooting Guide
If you are using a ‘Japan Unlimited v1’ SIM that was purchased before Oct 12th 2021 however, please follow the troubleshooting steps below –
Before following the steps below, please check the coverage in your area as Softbank may be performing maintenance which could be causing some temporary connectivity issues.
You can find Softbanks maintenance list and the effects it will have on your area here – Softbank maintenance schedule
If your are isn’t listed or the maintenance has been completed and you are still unable to call, text or use data then please follow the steps below;
1) Update your Android Operating System
2) Update the security on your phone
3) Complete all phone manufacturer system updates ( These are separate to the Android updates ).
If you do not know how to complete steps 1-3 please contact your phone manufacturer for guidance.
If your issue persists after completing steps the above steps, please;
1) Reset your network settings ( Usually by going to Settings – About – Reset – Network Settings – Reset )
2)Switch off your phone remove any SIM Cards installed in your device and leave your phone switched off for 5-10 minutes
3) Reinsert our SIM Card into SIM Slot 1 and leave slot 2 empty ( If your phone is dual SIM ).
Note: If your device is eSIM compatible, please ensure any eSIMs on your device are disabled ( not deleted ).
4) Switch your phone back on and wait a few minutes to see if your phone establishes a connection to Softbank
If your device does not establish a connection please check the following;
1) Network type/mode is set to 4G/LTE
2) VoLTE is enabled
3) The correct APN is installed
Name: Mobal
APN: plus.4g
Username: plus
Password: 4g
MCC: 440
MNC: 20
Authentication Type: PAP or CHAP
APN Type: default,ia,mms,supl,hipri
Bearer: LTE
APN Protocol: IPV4/IPV6
APN Roaming Protocol: IPV4/IPV6
If you have tried all of the above we would suggest contacting the service provider/retailer you purchased the phone from originally to check that it is capable of using VoLTE in Japan OR try using your SIM Card in an alternative device.