Unable to import SSH key

I’m having a weird issue with the SSH key import function. I’ve imported several keys to my vault before, but when I try to import a particular key the key passphrase prompt resets after I input the passphrase. I give it the passphrase, and it just asks for it again. And again. And as many times as I give it. I can’t tell if the app thinks the passphrase is correct, or incorrect. I know it is correct though.

The key in question was created with the Termius Android mobile app. I believe it’s an Open SSH key, but maybe it’s weird somehow? It certainly looks like one at least. I do know that it’s an ed25519 key at least.

Hope someone knows how to fix this. Thanks in advance.

Was able to import the key after using ssh-keygen to convert it to PEM format.

Thanks to the person who replied with that idea, but then must have deleted their comment.