Project does not work

I am working on a Free Code Camp Backend Project: exercise tracker.
In local development it works great, but as I upload it to Glitch, it doesn’t work. I have the page come up, but when I post data, it just loads and loads, but nothing happens, until it tells me to contact Glitch support. And I get no error messages.

That is weird, I tried getting the headers in the command prompt with no luck. You should report this to glitch.