This field can be updated in ir_property table, to get all property_payment_term_id values for all partners use the below query:

select * from ir_property ip where name='property_payment_term_id';

You can update it for all partners as below:

update ir_property 
set value_reference ='account.payment.term,1'
where name='property_payment_term_id';

Also you can change it from Odoo, enable developer mode and go to settings -> Technical -> Company Parameters and then search for name  property_payment_term_id  and you can update it from there!