Update record custom function not working

Update record custom function not working

Hello,

I'm trying to code my first function, which is super simple: upon clicking the button, I want to call a custom function which will update the Deals' record field ''Nom acheteur'' with the value ''Anges Immobiliers''

My code: 

deal_id_str = deal_id.toLong();
acheteur_AI = Map();
acheteur_AI.put("Nom_acheteur","Anges Immobiliers");
update = zoho.crm.updateRecord("Deals",deal_id_str,acheteur_AI);
return '';
(see screenshot 3)
deal_id is a parameter linked to the Deals field 'Deal ID'

I tried to use the module name ''Affaires'' instead of ''Deals'', vecause my CRM is in French. It didn't work.

I have no idea what's going wrong. Please help.

Thanks!