iCloud Backup

I have bought a new phone recently, and I had Icloud+ on my old phone, so when I started the new phone and connected it now I have everything.

When I checked the Icloud+ storage I found out that in the iCloud backup I have 2 backups, one from each phone with the same exact size. So is it ok to delete the old backup as I now have it included in the new backup from the new phone or will I lose the data from the old phone ?

Thank you