I got this function that works in harpoon:

        function()
          local index = require("harpoon.mark").get_current_index()
          if index ~= nil then
            local config = require('harpoon').get_mark_config()
            table.remove(config.marks, index)
            local global_settings = require("harpoon").get_global_settings()
            if global_settings.tabline then
              vim.cmd("redrawt")
            end
          end
          require("mini.bufremove").delete(0, true)
        end,

This function removes harpoon mark and also deletes buffer using mini.bufremove.