My hard drive containing the folders mapped to my local drive was broken, so I reinstalled Dropbox on another hard drive on my computer. But when I wanted to remap the folders to the local file explorer, there was a problem. Specifically, I wanted to map the folders to the local drive and save the data to the cloud, but I couldn't do it. I could only download the data to the local hard drive to see the folders saved in the cloud in the local file explorer; that is, I couldn't "save data only to the cloud" when I right-clicked my mouse.
I use a Windows 10 laptop, and my email account is in a family group.