While checking on different forums, I find someone suggesting to issue the following command in terminal:
log show --info --style compact --predicate '(subsystem == "com.apple.TimeMachine") && (eventMessage like[cd] "Failed * acquire device lock assertion*")' --last 24h
after few seconds, I got the following:
Timestamp Ty Process[PID:TID]
2024-09-29 18:02:52.849 E backupd[54103:292ab9] [com.apple.TimeMachine:FileProtection] Failed to acquire device lock assertion for '/Volumes/com.apple.TimeMachine.localsnapshots/Backups.backupdb/iMac-M1/2024-09-29-171018/Data/Users/donato/Library/Containers/com.apple.findmy.FindMyWidgetPeople/Data/SystemData/com.apple.chrono/timelines/com.apple.findmy.FindMyWidgetPeople/systemSmall---2695494529729235827----164.00w--164.00h--20.00r--0f--0.00t-0.00l-0.00b0.00t.chrono-timeline' (assertion state: <dropped>), error: Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"
2024-09-29 18:06:23.246 E backupd[54103:292ab9] [com.apple.TimeMachine:FileProtection] Failed to acquire device lock assertion for '/Volumes/com.apple.TimeMachine.localsnapshots/Backups.backupdb/iMac-M1/2024-09-29-171018/Data/Users/donato/Library/Containers/com.apple.findmy.FindMyWidgetItems/Data/SystemData/com.apple.chrono/timelines/com.apple.findmy.FindMyWidgetItems/systemSmall---3453820889416213992----164.00w--164.00h--20.00r--0f--0.00t-0.00l-0.00b0.00t.chrono-timeline' (assertion state: <dropped>), error: Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"
There is an issue, "Operation not permitted", with FindMyWidget?
I get the same error on both my macs on Sequoia, an iMacM1 and a MacBookAirM2.
I closed the FindMy Widget on both macs. Let see what happens...
PS: someone else reports that booting into safe mode and then back fixes the problem. Will try this one too...