Power cycler is supposed to give you 1-2 extra charged strikes. However if you use a charged push attack and then try to immediately push attack again the second strike will cancel the weapon’s charge.
Any other combo of attacks like push attack-light-light, push attack-heavy-heavy etc all work normally and you get the full number of charged strikes.
EDIT: This bug can also happen if you try to chain into the push attack after doing a charged light or charged heavy.