No backup Option

The problem is after owning this WD My Passport device - Backup is no longer an available option.
There is NO tab, no action for it… nothing. Suddenly I no longer can backup. I have used less then 1/2 the available space. I have had the option until 2 months ago. I have changed nothing knowingly. How can i backup when the option is no longer available?
Using on a Macbook Pro


Is the drive connected to the Mac directly or wirelessly?

What backup software are you using with the drive?

It is connected as always. I have not found a way to backup in a month. When you right click the word “Backup” doesn’t appear. As for backup software? I don’t know… I only use the passbook and whatever I needed to make it work before. I tried again today. The word backup isn’t anywhere. What happened? I am not a geek & I don’t mess with anything

Sorry - connected via usb