In order to retain 100% response rate you must respond to all first messages from new potential clients within 24 hours. That is the only criteria for ensuring 100% response rate and it is therefore very easy to do.
The only way to improve your existing response rate is to ensure you respond to people when they message you. Your response rate is actually terrible and I believe that Fiverr will take your response rate into consideration when displaying search results.
Therefore by not replying to people you are destroying your business.
Why is that nice? The op has a terrible response rate and was asking for help.
So, you’re encouraging people to try and cheat the system? That’s your advice?