How to remove the backup failed notification?

I don't want to backup my data to icloud and never did it. After I manually backup my old phone to computer and transfer it to new phone, for some reason, the new phone's backup setting turned on and try to backup my phone to icloud. It's not enough space for sure. So I go notification said backup failed.

I don't want to backup to icloud but even I turned off backup. The notification still showing up. It's red 1 shows on the setting icon, very annoying.

Someone said I must successfully backup once before this icon desappear, I tried to turn off everything on backup settings and trigger an icloud backup, but still it's telling me backup failed space not enough.

I don't want to backup to icloud, anyone can tell me how can I remove this backup failed notification?