Welcome to Smogon! Take a moment to read the Introduction to Smogon for a run-down on everything Smogon, and make sure you take some time to read the global rules.
I have the same problem in two devices:
Operating system: Windows 11 (pc) / Android 13 (Smartphone Xiaomi)
Web Browser: Chrome 119.0.6045.105 (pc) / Chrome 119.0.6045.66 (Smartphone)
Have you tried other browsers? Incongnito mode in Chrome and app for windows work
When did this problem start...