All present and correct.
Did you try the consumption with the DHW switched off only and then the UFH switched off only.
The UFH should be the easiest to check out, locate the (red) expansion vesse (or vessels) then locate the filling loop, some filling loops have a flexible hose with shut off valves at both ends, ensure both of these shut off and slacken the hose off at both ends to ensure no water passing. Other systems have a auto fill system where a pressure reducing valve set to 1.0bar keeps the system pressed up, this also has a isolating valve before the pressure reducing valve, shut this.
DHW: There should be a isolating lever or gate valve on the cold mains suppy to the cylinder, shut this.