A Microsoft file hosting and synchronization service.
This seems to have started after Samsung switched their online storage to OneDrive. If you go to the settings in the Gallery app, you will notice that "Sync with OneDrive" is enabled. It however doesn't seem to work. I have an S9 and the switch happened sometime in May. My photos haven't been synced since. This article suggests some troubleshooting steps but I still can't get photos and videos in my gallery to sync using the Gallery app. https://support.microsoft.com/en-us/office/samsung-gallery-and-onedrive-99c4e77b-8e63-4ddc-aede-19f81acee1a3
Unfortunately, you cannot simply disable Gallery syncing by toggling the setting. You must disconnect your Samsung account from OneDrive using the steps in the above article. After disconnecting, go back into the OneDrive app and re-enable Camera upload.
This worked like a charm once I disconnected the Samsung account from OneDrive. The "Camera Upload" option reappeared in settings. Didn't even have to restart the phone. THANK YOU!
To disconnect your Samsung Gallery from OneDrive
If you want to stop the Samsung Gallery app syncing photos to OneDrive and remove the Samsung data sharing permissions to your Microsoft Account, you'll need to edit how you sign-in to Microsoft:
1) Open your Microsoft Account's Additional security options.
2) Next to Samsung account, select Remove.
3) On your mobile device, go to Settings > Accounts.
4) Scroll down and select your Samsung account.
5) Tap Apps and services then Connected services.
6) Remove your Microsoft account from the list of Linked accounts.