Late reply, maybe a bit simplistic: 

– delete the template 

– remove the email from the template

Hello Diana Garcés Martínez,

In Odoo Enterprise for subscription module, there is one Schedule Action : 'Sale Subscription: generate recurring invoices and payments'.

This scheduler generates automatic invoices for Subscriptions and also add payment notification to customer.

If you don't want to sent notification message to customer than you can deactivate the Schedule Action.

Hope this Helps,

If you need any help in customization feel free to contact us.

Thanks & Regards,

Email:  odoo@aktivsoftware.com           

Skype: kalpeshmaheshwari

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