ok my query is for instance you can take sale module odoo16 as example
if the user create the  quotation it stay in  quotation state i want that every 3 months after the date_order user get the reminder notification with note call the client with  quotation id so that i can know which client i need to call and for what  quotation this notification should be come again after next 3 months ..... till the  Quotation state change to sale.
i know it might need customization from backend if yes please share the sample code for sale module i will use it for my customized module.

thanks.