disklabel won't write configuration.

I am usinOpenBSD 7.6 GENERIC.MP#338 amd64

I have a 1 TB disk I formatted under Linux. I wanted to change the disklabel from:

sd1> p
OpenBSD area: 64-1953525104; size: 1953525040; free: 0
#                size           offset  fstype [fsize bsize   cpg]
  c:       1953525167                0  unused                    
  i:       1953525040               64 unknown

to:

sd1> m i
offset: [64]
size: [1953525040]
FS type: [unknown] ext2fs
sd1*> p
OpenBSD area: 64-1953525104; size: 1953525040; free: 0
#                size           offset  fstype [fsize bsize   cpg]
  c:       1953525167                0  unused                    
  i:       1953525040               64  ext2fs                    
sd1*> w
disklabel: DIOCWDINFO: Input/output error
disklabel: unable to write label
sd1*> x

I get the above "disklabel: unable to write label" message. What am I doing wrong?

If I leave the disklabel alone, then the disk mounts just fine.

# mount -t ext2fs /dev/sd1i /mnt