The whole connection matters
Your internet plan is only one part of playback. Wi-Fi signal, household traffic, device performance, the player and the stream source all affect the result. Test where you actually watch, rather than beside the router only.
When a stream buffers
First check whether other internet apps work. Restart the player, stop other simultaneous use of the same subscription and try another available channel. If Ethernet is possible, it can help identify whether Wi-Fi is the issue.
HD and 4K labels
A device may support 4K while the selected programme is supplied at a lower resolution. Picture quality depends on the source and licensed package as well as your screen and network. Ask about the specific content you want; no resolution label guarantees every title.
Useful information for support
Send your device model, app version, country, affected channel or title, time of the problem and error message. Hide account passwords and private payment information in screenshots. This gives support a clearer starting point than “it does not work”.