threaded=True

main.py

@@ -1,6 +1,7 @@
 from flask import Flask, request
 from app import judge
 from flask_cors import CORS
+import threading
 
 app = Flask(__name__)
 CORS(app)
@@ -18,7 +19,11 @@ def returnText(text):
     return f'The text is {text}'
 
 @app.route("/check", methods=["POST"])
-async def check():
+def check():
     comment = request.json['comment']
     result = judge(comment)
-    return result
+    return result
+
+if __name__ == '__main__':
+    
+    app.run(debug=False, threaded=True)