Delete Files on both: mobile phone and mycloud

hi, i am using mycloud os5 on my android mobile phone. i have switched the automatic backup on my mobile phone. It work. But: a lot of garbage is backed up. Wenn i delete some fotos direktly in the mycloud app - both folders will be synchronized und the whole garbage is back. How can i delete any fotos irretrievably?

Hi, this is the My Cloud Home (MCH) forum but you said you are using OS5 which is not MCH. Just in case this question is about MCH and for other readers, this is what support said back in 2018 regarding syncing with Google Drive which may be similar to the question being asked.