Key authentication in SecureCRT. Why doesn't it come out?

Question

SSH

Tell me one thing. It is necessary to connect from Windows to * nix-machine via ssh. I always used PuTTY for this, but then I decided to try the advanced SecureCRT client.
SecureCRT can generate keys in OpenSSH format, which means I don't need to use key conversion with "ssh-keygen -i -f".
Here I am generating keys in SecureCRT (screenshot), set the switch to "OpenSSH Key format"

The public key Identity.pub and the private key Identity are created. I, as not the first time working with this, I know that I should copy Identity.pub to the server and add it to .ssh/authorized_keys there, which I did, and keep Identity, protect it from copying as much as possible and use it for authentication with the server . But at the same time, when I try to connect to the server using SecureCRT, for some reason it asks me for a file with the pub extension, I ignore this requirement, because I know that I still need a private key for authentication, I slip it Identity. The answer is "Public-key authentication with the server for user username failed". Tried swapping keys, same thing.