Account sync on a Galaxy S20, a phone from 2020 on its final software, fails for three kinds of reasons: leftovers from years of accounts, power rules that put apps to sleep and cloud services that have changed since the phone was new. Open Settings, Accounts and backup, Manage accounts, and look for duplicate accounts, an account with a warning or one that was added long ago and may need a fresh sign-in.
The checks in more detail
Tap an account and check each data type's switch and its last sync time; a time that is days old is a blocked sync. Tap Sync now, and watch for an error. Remove an account that you no longer use, and, if one needs a fresh sign-in, remove it and add it again after confirming that the data is safe in the cloud. Samsung changed its cloud arrangements while this phone was in use. Photo sync from Gallery went to Microsoft OneDrive, while Notes and other Samsung data stayed in Samsung Cloud,
so a Gallery that is not syncing is a OneDrive matter, and Notes depends on the Samsung account. Check both. On a phone this old, the battery rules are strict: in Settings, Battery and device care, Battery, Background usage limits, move the sync apps out of the sleeping and deep sleeping lists. Data saver can stop background data, so check that in Settings, Connections, Data usage. Other things to check are the date and time, which must be automatic for sign-in to work,
and the free storage on the phone and in the cloud account, since a full account stops new data syncing. Update Google Play services and the Google app in the Play Store, since an old version can fail with newer account systems. Restart the phone. If one app, such as Calendar, fails, clear its cache and check its own sync switch. Because the S20 is old, a factory reset, after a full backup, sometimes cures stubborn sign-in faults. Contact the account's support pages for lockouts.
Differential
Likely causes of “Samsung Galaxy S20 family photos, contacts, messages or account data will not sync”, and how to tell them apart
- 1
A duplicate or stale account
What separates it Sync errors or a warning
How to confirm Remove the extra account and sign in again
- 2
Gallery syncing to OneDrive
What separates it Photos do not appear elsewhere
How to confirm Check the OneDrive sign-in
- 3
Battery limits that sleep the app
What separates it Sync works only when the app is open
How to confirm Move it out of the sleeping lists
- 4
A wrong date or old Play services
What separates it Sign-in fails
How to confirm Set automatic time and update Play services
- 5
A full cloud account
What separates it New data does not save
How to confirm Free space
Before you touch a setting
Record this first — changing settings destroys the evidence
- Which accounts exist
- The last synced times
- Whether battery limits apply
- The cloud storage state
Try in this order
0 of 6 completedList the accounts
ReversibleIn Manage accounts.
Remove duplicates
ReversibleAnd re-add if needed.
Check Gallery and OneDrive
ReversibleFor photos.
Free apps from sleep
ReversibleIn battery settings.
Set automatic time
ReversibleAnd update Play services.
Restart
ReversibleAnd test.
Model-specific
What is true of this model and not of its siblings
- Final software
- The S20 will not get new fixes.
- Two clouds
- OneDrive and Samsung Cloud.
Stop boundary
When this stops being a self-service repair
- !If sign-in fails, use the account's recovery page
- !If one app fails, contact that app's support
Evidence ledger
Sources behind this answer
Exact questions
Common questions
Why is my old S20 not syncing?+
Stale accounts, sleep rules or an old service.
Where do photos sync?+
To OneDrive.
Do Notes use Samsung Cloud?+
Yes.
Should I reset?+
Only after a full backup.