2 days ago I buy new S2 MK3 and registered new product in my account. I want to return this product in store. How I can delete serial number from my account?
You can transfer the serial but I do not think that you can delete the product . For that you will have to ask N.I. Account Support .
In case that you need guidance contacting support : How to contact NI Support and How to get in touch with our Customer Care