A simple checklist when a streaming video buffers

First determine whether the issue affects one programme, one device or the whole connection. That distinction helps you choose a useful next step.
Compare carefully
Try another title and note whether it plays. Check if other devices are using the connection for a large download. If the player offers a lower quality setting, test it and observe whether playback stabilises.
Record the error
Write down the title, approximate timestamp, device, app version and error text. Do not publish account details or verification codes.
Avoid unnecessary resets
Start with reversible steps such as closing and reopening the app. Before clearing data or reinstalling, consider that downloads and sign-in information may be removed. Contact official support if the problem persists.