how should I compare two strings case-insensitively

Question

I am making a little rock paper scissors game in rust as a little mini-project while I learn the language. I have made the code below, but it seems that no matter what I do, it always prints "Invalid Response."

My current code:

fn start_next() {
    thread::sleep(time::Duration::from_secs(3));
    rps();
}

fn rps() {
    let rk = String::from("rock");
    let pp = String::from("paper");
    let sc = String::from("scissors");
    let end = String::from("end");
    
    let mut guess = String::new();
    println!("Choose one (\"end\" to quit):\n- rock\n- paper\n- scissors");
    
    io::stdin().read_line(&mut guess).expect("Unable to read line");
    let aichoice = ["rock", "paper", "scissors"][(rand::random::<u8>() % 3) as usize];


    // debug
    println!("\nAI chose {}", aichoice); 
    println!("You chose {}", guess);
    

    
    if guess.eq_ignore_ascii_case(&rk) {
        match aichoice {
            "rock" => {
                println!("Your moves canceled out.");
            }
            "paper" => {
                println!("Paper defated your rock.");
            }
            "scissors" => {
                println!("You defeated scissors");
            }
            _ => {}
        }

        start_next();
        return;
    }
     if guess.eq_ignore_ascii_case(&pp) {
        match aichoice {
            "rock" => {
                println!("You defeated rock.");
            }
            "paper" => {
                println!("Your moves canceled out.");
            }
            "scissors" => {
                println!("Scissors defeated your paper.");
            }
            _ => {}
        }

        start_next();
        return;
    }
    if guess.eq_ignore_ascii_case(&sc) {
        match aichoice {
            "rock" => {
                println!("Rock defeated your scissors.");
            }
            "paper" => {
                println!("You defeated paper.");
            }
            "scissors" => {
                println!("Your moves canceled out.");
            }
            _ => {}
        }

        start_next();
        return;
    }
    if guess.eq_ignore_ascii_case(&end) {
        return;
    }
    
    println!("Invalid response");
    start_next();
}

(yes, ik this if chaining kind of sucks, but I am trying this because it wouldn't work with string.to_lowercase() and match)

I had previously, like I mentioned, tried to use a match case statement to do it, but it had the same results.

My previous code was something like this:

let mut guess = String::new();
println!("Choose one (\"end\" to quit):\n- rock\n- paper\n- scissors");
    
io::stdin().read_line(&mut guess).expect("Unable to read line");

let aichoice = ["rock", "paper", "scissors"][(rand::random::<u8>() % 3) as usize];
let guess2: &str = &*guess.to_lowercase();

match guess2 {
    case "rock" => {
        ...
    }

    case "paper" => {
        ...
    }

    case "scissors" => {
        ...
    }

    case "end" => {
        return;
    }

    case _ => {
        println!("Invalid Response");
    }
}

thread::sleep(time::Duration::from_secs(3));
rps();

My guess is I either made some random mistake both times or have something wrong with my Rust installation.

I also tested with my previous code and to_lowercase() was working, just something with comparing strings that I don't understand.