Back up existing photos to Google Drive?

I switched from Dropbox to Google Drive on my Huawei. So I installed the Google Photos app and enabled the backup via Google Drive.

Unfortunately, only the new photos are being backed up, which is now happening. Do I have to manually copy the existing photos to Google Drive or have I overlooked a setting?

That would have to help, explains everything: https://support.google.com/...roid&hl=de

I already found this guide.

It means synonymous with me on Google Photos "backup completed" But it was not backed up a photo that is older than the time I have activated the backup. All photos will be shown under Google Photos…