How to change the hours of listenig

I made a mistake! I added 40 hours instead of 40 minutes. Hou can we the hours of listening?
Are threr anyone who can understand French? I write my English very bad.

Je me suis trompé d’ajouter l’heure d’écoute; 40 heures a lieu de 40 minutes. Comment puis-je changer l’heure d’écoute?


a lieu→au lieu

you can reduce with a -40 and than add the correct time

Thnak you very much for your advice.
Je vous remercie de votre advice.