Check that OneDrive is signed in by clicking arrow in bottom right & hovering over the cloud :
if cloud is blue like this, you are signed into OneDrive proceed to step 3:
if its grey with a line click it to sign in:
if there is no cloud please start OneDrive via the Windows/Start button or restart your PC then check its status again
if cloud says 'Signing in' give it a couple minutes then check its status again, if its still like this you can right-click to exit it, then restart it:
If asked to backup known folders (you might not be) select Yes and/or Start backup
After restart verify VPN is connected & OneDrive shows its signed in then you should be good to go:
FAQ
OneDrive isn't working and/or I can't access my files & don't have time to troubleshoot: Nexus Service Desk article: OneDrive: alternative ways to access your files. Please do inform IT when OneDrive isn't working, as it's very important.