Reset backup data

I remove the Avast backup folder from my Google Drive because there were old files inside them and to much work to delete them one by one.
I want to make a full backup of my Samsung S5 but Avast Mobile backup only makes backups of files not backupped before.
Can I somehow reset the “backup bit” so Avast Mobile Backup thinks the files aren’t backup up before and will backup them all on my Google drive?

Found out if I remove the connection with my Avast account en reconnect it, I can backup all my files on my Samsung S5.
Isn’t there an easier way to force a full backup of your device?

FAQ: https://www.avast.com/faq.php?article=AVKB125