Hi Jay Pfaffman, thank you for your support
Here are my website logs: https://nghienseo.com/logs/ (also because I’m new to Discourse so I don’t know how to look at /logs to find the error I’m having)
I have attached the Plugin I’m using. It’s true that a few days ago I installed 2 more plugins: Stopforumspam vs Calendar.
Currently I don’t have any solution to fix it, please support me. Thank you very much!