How to remove added ringtone

I have added a new ringtone to the ringtones list in Settings->Sounds->Phone ringtone>Add ringtone. After that I can see the same ringtone file in Ringtones folder of Internal storage. I need to remove this ringtone? For that I have deleted that file from folder. But, the ringtone is still running there. How to remove it. Device: Moto X4 Oreo 8.0 (non rooted)