Huawei
Enable or Disable Automatic Data Backup auf Huawei
Huawei phones can save a backup to external storage once a week without any manual action, but two conditions have to be met at the same time. The device needs to be connected to a charger, and the battery has to hold at least 75 percent capacity. If either condition is missing when the scheduled time arrives, the backup simply gets skipped, and there is no error message to warn you.
This behavior is intentional. Writing a large backup file drains the battery and puts extra load on the storage, so Huawei ties the process to a safe power state. It also explains why a backup that worked last week can suddenly stop appearing, especially if you changed charging habits or let the battery run lower overnight.
To check or change the setting, open Settings ➔ System & updates ➔ Backup & restore ➔ Data backup ➔ External storage. Choose the target, either Memory card, USB storage or Shared folder, then enable or disable Auto-backup. When enabling it, select the data you want included and confirm with OK, then confirm the setup again with OK.
Disable auto-backup if you back up manually to a different service, or if the scheduled write is interfering with storage space on a full memory card. For everything else, leaving it on and simply keeping the phone charged overnight covers most cases.