Error with libcrypto when launching openssh server

Hi everyone!
I'm having some problems while configuring OpenSSH in OpenWrt. I've satisfied all the dependencies of the package, but when i try to start the openssh server it fails. I have launch directly /usr/sbin/sshd so I can see the debug traces:

Unable to load host key "/etc/ssh/ssh_host_rsa_key": error in libcrypto
Unable to load host key: /etc/ssh/ssh_host_rsa_key
Unable to shield host key "/etc/ssh/ssh_host_ed25519_key": error in libcrypto
Unable to load host key: /etc/ssh/ssh_host_ed25519_key

I have tried to regenerate the keys, but I keep getting the same error.As additional information, I have no problem running dropbear, it works perfectly and I can connect, but the project requirements specify that I must use openssh. Does anyone know how I can solve the problem?