Hello, the rest api gets called twice exactly at the same time causing the sales order document number to duplicate in NetSuite, even though they have different internal ids. Is there any way to stop this from happening?

why is it getting called twice? internal ids are created automatically by NS and are unique so if you call it twice you will in fact get two documents created. you can use externalid and this should limit the second one from being created since it has to be unique. doesn't necessarily solve the issue though because now you will have a lot of dup errors being returned