second page flask template not found 404 error

I'm learning Flask for the first time and I can't get the local host to display the second page. I put 2 pages in the templates folder so far, the index page and the second page. Here's the code:

from flask import Flask, render_template

app = Flask(__name__)

@app.route('/')
def home():
    return render_template('home.html')

@app.route('/about')
def about():
    return render_template('about.html')



if __name__ == '__main__':
    app.run(debug=True)