how can someone block me from leaving them After leaving me negative feedback?

[lady.stark]

Do you mean you cannot leave negative feedback for a buyer? If that is the case, eBay took away the possibility of leaving a negative comment to a buyer many years ago. And if you leave a "false positive", buyer can have it removed.

As for the negative comment you received, you can respond to the comment, which I see you did. You can also try to contact the buyer and convince him/her to revise his feedback. In some instances, the negative can be removed by eBay if you ask for it, but it has to be for specific reasons. Unfortunately, I do not think yours fall under those criterias.

[pjcdn2005]

You should be able to get the negative removed if you can show them with online tracking that the item was shipped out within your handling time. Otherwise, the negative is likely to stay there.