Your boiler is currently in the process of lighting the flame to heat your water, which is a normal part of its operation.

DHWmode:Ignition

What causes this fault?

This fault occurs when the boiler's control system attempts to start the heating process but fails to detect a stable flame through the ignition electrodes. The most common reasons are a worn-out spark probe that can no longer create a spark or a faulty gas valve that isn't delivering enough fuel to the burner.