I have been dinged on the star seller status for not responding to my buyer within 24 hours. When reviewing my messages the buyer sent me an email stating she was happy and would leave a review when possible. I did not respond to this as she was not asking a question. We had previous communications that were responded to immediately. Another one was a response I sent directly to the customer by email as per their request. Is there any way to remedy these? All of my responses are generally done immediately.
If it's for the current rating period, you can mark them as SPAM, retroactively.
You have to reply to all messages, or mark them as spam. That is the criteria for star seller.