To create a login for the supplier backend you should first create a supplier and then a supplier login.
Create a supplier
Step 1 – Goto Supplier/Hub page in Admin backend
Step 2 – Create a supplier by filling the mandatory fields
Creating a supplier login
Step 1 – Goto Supplier user/Hub user page in Admin backend
Step 2 – Search with the supplier login email added while creating the supplier and then open the ID to set a password for the login
Use the above-created login and password to login to the supplier backend and start creating other users and drivers for the supplier directly from the supplier backend. The users and drivers created under a supplier backend will have access only to that supplier. Example supplier backend URL – supplier.companyname.com