Identify the symptom
Write down whether the issue is buffering, a login error, a blank screen or one unavailable stream. This prevents random changes.
Check the network
Run a speed test near the device, restart the router and compare Wi-Fi with ethernet or another trusted connection.
Check the device and player
Update the operating system and player, clear the cache and confirm that automatic date and time are enabled.
Contact support with details
Share the device model, player name, time of the issue and exact error message. Never share passwords publicly.