FYI that I do not work for NOW, I am simply a NOW customer trying to help I am a Community Contributor This means that I know a lot about the service and like you I am still a customer. For any account issues you’ll need to contact staff via customer support.
S4C Clic is part of S4C, not Channel Four. NOW TV need to offer the S4C app for full service in HD. SOME S4C content IS available on the BBC iPlayer in SD, check there if the programming you are wanting happens to be available there.