what else can I try to backup my phone?
I followed backup steps: plug in, turn on backup, Lock Screen --- not working for me. anything else I can try?
iPhone 11 Pro Max, 16
If you're trying to backup your iPhone content to iCloud using wifi, your iCloud storage may not be enough to host your backup.
Check your iCloud storage in Settings>[your name]>iCloud...
Regards
Giulio