Public key for /etc/ssh/whatever does not match private key - but it does

When I start my ssh service (on a Devuan Chimaera Linux box), I get the warnings:

Public key for /etc/ssh/ssh_host_rsa_key does not match private key
Public key for /etc/ssh/ssh_host_ecdsa_key does not match private key
Public key for /etc/ssh/ssh_host_ed25519_key does not match private key
Public key for /etc/ssh/ssh_host_rsa_key does not match private key
Public key for /etc/ssh/ssh_host_ecdsa_key does not match private key
Public key for /etc/ssh/ssh_host_ed25519_key does not match private key

So, I checked the RSA keys using the method described here: How to check if an RSA public / private key pair match ... and they do match.

What's going on? I should mention SSH'ing using RSA keys seems to work.