Hot Water intermittent

Hi all

I’ve inherited a tado system and am really struggling with some basics. There is a receiver, bridge, wireless thermostat and one radiator control. The rest of the house is on TRVs. I’ve not really had to explore heating yet but it seems I can get this firing up via the thermostat. However, hot water is a different story - we have a gas boiler and a cylinder. There is no control that I can see on the app for hot water. If I press the button 3 times on the thermostat it shows a graphic of hot water which I can switch to on. When I do this, I get hot water - great. But then at some point, it resets back to off. I don’t know when or why, but I’d love to stop this happening, or at least understand how to control the timing so I know that the kids will get to have a warm bath in the evening rather than the cold baths they’ve been encountering!!

I tried playing around with the manual control function in one part of the app but the upshot is that I can no longer control the water through the thermostat and can’t get any hot water.

Finding this deeply frustrating and would be incredibly grateful if anyone has any tips!

Thanks
Stephen