Hello,
I am currently testing osTicket before deployment for our company, the setup process was smooth and the API usage is pretty straightforward, after coming back into the office I presume the session has expired and I was required to log in again to the admin panel but I kept getting the Authentication Required error, I found this post Ref. post. After clearing the cookies I was able to log in again, but the provided solution for this error does not apply in my case (Disabling Bind Agent Session to IP, as it was never enabled in my case).
Not sure what info to provide so here are some hopefully relevant screenies.

