resp cannot be resolved | Java Servlet: programação web Java

Eu tento abrir o caminho http://localhost:8080/gerenciador/oi mas aparece a mensagem:

java.lang.Error: Unresolved compilation problem: resp cannot be resolved

br.com.alura.gerenciador.servlet.OiMundoServlet.service(OiMundoServlet.java:20)
jakarta.servlet.http.HttpServlet.service(HttpServlet.java:770)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

Meu código a seguir:

package br.com.alura.gerenciador.servlet;

import java.io.IOException;
import java.io.PrintWriter;

import jakarta.servlet.ServletException;
import jakarta.servlet.annotation.WebServlet;
import jakarta.servlet.http.HttpServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;

//oi
@WebServlet(urlPatterns = "/oi")

public class OiMundoServlet extends HttpServlet {

    @Override
    protected void service(HttpServletRequest arg0, HttpServletResponse arg1) throws IOException {

        PrintWriter out = resp.getWriter();
        out.println("<html>");
        out.println("<body>");
        out.println("Oi mundo!");
        out.println("</body>");
        out.println("</html>");

    }

}