How to delete a file

Try restarting the phone. But it is possible it isn't there and you just are getting a false reading that it is, or it is not a file you can delete. There are many files you can't remove on a phone.
Jul 29, 2018

1. ) Try using other explorer and do it again.
2.) Use PC to delete.
3.) Install Antivirus and check does it belongs to a virus.
4.) Backup and format.

Sorry for if think was unusual tips but I tried to help.