How do I get my Passport for Mac to overwrite older update

My computer has just reached over the halfway point (555GB) and MY 1TB Passport can’t update anymore due to lack of memory. I really only need one update anyway. It seems pointless to get a 4TB since I’ll only have three backups before that fills up too. Has anyone just wiped it clean and started over with success? Thanks

If you are using Time Machine for backup, all you can do is to erase the drive and start over the Time Machine backup but not overwrite overwrite.