I cant access my login with postman

Hi there, 

Postman is a powerful HTTP client for testing the QuickBooks Online API by displaying requests and responses in manageable formats. It's important you get the support you need so you can create invoices and get ahead with your work. 

I want to make sure you get the support you need with this. I recommend reaching out to our Developers Support team using this link here. You can also reach out to QBO support using these contact details:

• Phone and Chat: Click Contact Us to learn how to reach phone and chat support.
• Schedule a Callback: click (?)Help in the upper right > click Contact Us > explain your situation > click Let's Talk > choose Get a callback (Note: Callback hours are the same as regular phone hours.)
• Social Media: Facebook, Twitter, and Instagram from Monday to Friday between 9 a.m. and 8 p.m. ET

Let me know if this helps.