The ajax requests are redirected incorrectly on your server
1. The initial ajax request returns a status of 302, which means it's redirected: https://i.imgur.com/bdY2iIL.png
2. It initiates another 2 requests to the same file (???) and returns the whole page as result, thus no event handlers were executed: https://i.imgur.com/8ydhcnw.png
You probably have an incorrect or malfunctioning .htaccess configuration file, or one of the rules is redirecting incorrectly. I recommend checking that, or reverting it to the default.
This can be caused by the virtual hosts file as well on your server configuration, however it's most likely a .htaccess related issue.
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