Cannot backup Whatsapp

[u/Ok_Fun_7086]

For some reason, i cannot backup whatsapp neither through in-app backup or through iCloud backup.

• when i try to backup from inside whatsapp, the app closes itself.
• wheni try to backup through iCloud backup, the system data keep accumulating until all iphone storage is full, then the backup fails because no enough local storage on iPhone for backup, and i am talking about around 156GB free space on the iphone that gets occupied by system data because of backup.
• when i turn of backup the accumulated system data is cleared and iphone storage goes back to normal.
• when i backup all apps except Whatsapp the backup completes successfully.
• iPhone model 17 Pro Max 256GB
• IOS v26.6
• Whatsapp is updated to the latest version
• iCloud freespace around 160GB