"Your device clock is out of sync." Your clock matches atomic time. Your seller's clock is wrong. They blame you.
Here's a contrarian observation: time sync errors are often server-side. A British IPTV reseller who checks their own NTP configuration will find the real problem. A lazy seller blames your device. A careless seller's server clock drifts.
In most cases, a good seller's clocks are accurate within milliseconds. A bad seller's clocks drift. A terrible seller's clock is off by minutes.
What actually works is asking: "What NTP servers do your systems use?" A good IPTV reseller UK answers. A bad seller says "standard" — which means they haven't checked.
Let me give you a real example. A user's British IPTV showed clock sync errors constantly. His clock was fine. The seller's server was 5 minutes off. They fixed it after he proved it.
Most operators find that time sync errors are embarrassing. Sellers who blame users are adding insult.