How to change ignition battery on Cannon C60GCIK cooker?

Manual here:

https://www.hotpointservice.co.uk/lib/manuals/ch60gcik_gcis_gciw_19508818000.pdf

1) The manual makes no mention on a battery
2) The manual tells one how the cooker plugs into a mains electric supply. One would suggest this is how the igniter is powered. Not battery.
3) The fact that the grille and oven pilots are lighting would suggest there is little wrong with any electricity supply, either mains it battery.

It may be there is a problem with the ignition transformer, electrodes or cables.

Phgs
April 2020