The Kewtech KT63 user-manual shows that the maximum continuity result shows as 19.99kOhms, meaning that the conductors tested are open-circuit.
The scary thing is, ring-final circuits can still function as normal when a single live-conductor is open-circuit, presenting a danger of over-current on the remaining conductors. Conversely radial-final circuits will not function when a single live-conductor is open-circuit, resulting in a relatively safer mode of failure.
Check between all terminations to identify the fault.