Okay, I'll share here step by step how it's supposed to work. Then you can tell me where it doesn't behave as it should:

You sign in with Steemconnect

You allow Hybh access:

You tap import account (if it's the first time) and you add your username + private key (and if you want to login with a keychain password select keep the account on this computer) and tap get started:

You choose your own keychain password and tap get started:

You tap log in:

And you should be in! 😄