I have searched on the web for over two days now, and probably have looked through most of the online documented scenarios and workarounds, but nothing worked for me so far.
I don't know if anyone came to this issue while trying to test the outputted URL in browser but if you are using Postman and try to copy the generated url of AWS from the RAW tab, because of escaping backslashes you are going to get the above error.
Use the Pretty tab to copy and paste the url to see if it actually works.
I run into this issue recently and this solution solved my issue. It's for testing purposes to see if you actually retrieve the data through the url.
This answer is a reference to those who try to generate a download, temporary link from AWS or generally generate a URL from AWS to use.