What is /data/backup/ for on android and culd i delet the files in there (try to backup with TWRP)

I need to delete the files in that folder becouse i try to make a backup with TWRP of my system but the files (or just one of them) is abording my backup and i get errror 255

I:Error adding file '/data/backup/xwLBFGdSbAq4bs4zMw1ZvB' to '/data/media/0/TWRP/BACKUPS/4741abba/2019-08-18--12-41-39_lineage_dipper-userdebug_9_PQ3A190705003_bd/data.ext4.win000'

Fehler beim Erstellen der Sicherung. (Error while creating a Backup)

I:ERROR tarList for thread ID 0

Fehler beim Erstellen der Sicherung. (Error while creating a Backup)

I:InfoManager saving '/data/media/0/TWRP/BACKUPS/4741abba/2019-08-18--12-41-39_lineage_dipper-userdebug_9_PQ3A190705003_bd/data.info'

Prozess createTarFork() endete mit FEHLER: 255 (Proces endet with error: 255)

Sicherung fehlgeschlagen, bereinige Sicherungs-Verzeichnis (Backup faild, Clean ?Files?)

I:Copying file /tmp/recovery.log to /data/media/0/TWRP/BACKUPS/4741abba/2019-08-18--12-41-39_lineage_dipper-userdebug_9_PQ3A190705003_bd/recovery.log

the errors where parthely in german but i wrote a hopfully good enough translation behind them.

for the phone:

• xiaomi mi 8


• 256 GB (9% used)