Assuming nostr is just the platform! Which app do you use? Which algorithm you plugged to say which content comes up? 

 Your private keys are still protected right? The public key doesn’t matter. Issue a new one! I don’t understand! One is getting your food and wants to pay infinite interest back to you and you are not happy about it? The either return it back or get eliminated. In both cases what you have lended gets returned. Move everything to a private key. 

 Taken? They get milked unless return it back with all interest paid. Protect your identity under a private key. And wait.