Possible cause:
You haven't set "Gohiiki Rikishi" with each devices
You need to add rikishi to your Gohiiki with each devices, because Gohiiki rikishi's data is only saved in a device(not cloud).
* You can use Grand Sumo app with same status(Tanimachi or not) if you login to the Google Play Store with same Google Account and install the app in each devices.
If you have already add them and you cannot receive push notifications, please check "I can not receive push notifications".