paypal adaptive Authentication+failed.+API+credentials+are+incorrect

i'm testing the adaptive payment on sandbox mode. but i'm getting error=Authentication+failed.+API+credentials+are+incorrect

so, i would like to know where i get the password and signature for the sanbox? because on paypal developer website did not show.

my configuration is:

mode: sandbox

# Credentials for Classic APIs
app_id: APP-MY SANBOXAPP
username: [github]
password: WX4WTU3S8MY44S7F = DEFAULT FROM [github]
signature: AFcWxV21C7fd0v3bYYYRCpSSRl31A7yDhhsPUU2XhtMoZXsWHFxu-RWy = DEFAULT FROM [github]

sandbox_email_address: [github]