If the Google Photos app uses the Mobile Data instead of your Wi-Fi connection, then you can check the info below and learn how to force it to stop using your carrier network when backup your data usage.
Usually Google Photos will use Wi-Fi connection when backing up all your photos and videos, but there are some situations when the app is using the Mobile Data instead. The first thing you can try to change / apply would be to update the app to its latest possible version. Also, you should look for firmware updates, too. If a new update is available for the app, then you should install it first, then you can look for Android official updates. In case the problems are fixed after updating the app, then you don't need to follow any of the instructions presented below.
NOTE: open Google Photos app, open the app Settings screen> go to "Back up & Sync" and make sure that everything under "Cellular Data Back Up" section is disabled. If all those are disabled and the Photos continues to use Mobile Data instead of Wi-Fi, then you should try to apply the changes presented in the methods below.
Clear Google Photos app Cache and Data:
The app data might have gotten corrupted recently and that is why it is malfunctioning. The first thing you can try would be to clear the cache and app data from the Google Photos app. This step will not delete any photos nor videos you have stored on your device.
Here's how to clear the Google Photos app cache and app data:
- go to Settings.
- Open Apps list and find the Google Photos app - open it.
- go to Storage menu under the Google Photos app menu.
- first you have to tap "clear cache" and confirm.
- next you can tap "clear data" and confirm.
- relaunch the Google Photos app and test the backup functions.
If this doesn't fix the problem, then you should check the other methods below.
Boot Galaxy S9 in Safe Mode and Test Google Photos Backup:
The Safe Mode is a backup system used by all the Samsung Galaxy phones, and it can be used by anyone who wants to troubleshoot their devices and get rid of all the software problems they're having.
If the Google Photos is capable of backing up media files using the Wi-Fi when the Galaxy S9 is running in Safe Mode, then the problem might be because of a rogue app. Boot the phone in Safe Mode, test the Google Photos app and if it does work, then you have to start and remove the bad apps from your device. After you manage to remove an app you need to boot in normal mode and test Google Photos again.
Here's how to boot Safe Mode on Galaxy S9: press the Power button and wait for the Power options menu to load. Now you have to tap and hold the "Power off" icon, as it will turn into a "Safe Mode" one. Tap once the "safe mode" icon and wait for the Galaxy S9 to boot in normal mode.
When you're in Safe Mode first you should test the Photos app and see if the backup is working when using the Wi-Fi connection. If the issues are gone in Safe Mode, then you will need to start removing some apps you have installed recently as those might be preventing Google Photos from using Wi-Fi when backing up data to the cloud.
Uninstall and Reinstall Google Photos app:
Another thing you might want to try would be to remove the Google Photos application from your phone completely. Reboot the phone, then reinstall the app and see if that fixes the problem. Also, you can consider removing your Google account from your device.
If the problem persists you can try to remove your Google account from the device, and then re-add it and see if the Google Photos Wi-Fi backup works. Before getting to the next step you can tell us in comments more about the problems you're having, and we will try to offer support and prevent you from factory resetting your device.
Factory Reset the Samsung Galaxy S9 using Recovery Mode:
The last thing you should try in order to fix the problems your Galaxy S9 is having with Google Photos would be to Factory Reset the phone.
The steps below are going to remove all the installed apps and all the data from the internal storage of your phone, so you should create backups for all important files before starting the Factory Reset steps. Apply the steps below only if you know what you're doing, as we cannot be blamed in case you end up losing any data files.
Here's how to factory reset your Galaxy S9 device:
- power off the phone.
- press and hold simultaneously Volume Up + Bixby + Power buttons.
- release the buttons when the screen turns blue and an Android logo is shown.
- wait 30 seconds more for the device to load all Recovery options.
- select 'wipe data/ factory reset' and confirm process.
- reboot the phone in normal mode when you are done.
These were all the steps that you had to take in order to attempt and fix the problems your device is having with the Google Photos. If you need more help you should tell us in comments and we will help you. Also, if you have a better solution for the Google Photos app, then feel free to let others know too.