Data of Gohiiki Rikishi is saved within Grand Sumo app.
When you reinstall the app after you have once uninstalled it or restored your device to factory settings, the data of your Gohiiki is also be reset.
Add your favorite Rikishi to Gohiiki once again.
*If you are Tanimachi, restore your Tanimachi membership status at first.
How to restore Tanimachi