Start with one screen
Close other streams and large downloads for an initial comparison. Play one live channel and one on-demand title. Record the time, app version and what happens: a spinning loader, picture breakup, audio delay or an account error. These symptoms are not interchangeable and help support narrow the issue.
Separate Wi-Fi from the internet connection
Where your equipment supports it, compare a wired Ethernet connection with your usual Wi-Fi. Distance, interference and a congested wireless band can affect playback even when a speed test looks fast. Changing one thing at a time makes the result useful.
Repeat during the evening
A midday test may not reflect the connection when everyone is home. Repeat on a normal viewing evening with your usual household activity. Test more than one source; a single unavailable channel is different from every stream failing.
Send an actionable report
Share the device model, app, approximate time, connection type and affected channel with support. Ask the team to check the account and available server route. Do not assume a VPN always helps or that buying a faster broadband tier will solve every problem.