problem connecting with the paypal gateway. (CODE)560022

Hey guys,

i got this error when trying to make a pledge using the fundraising plugin.

"There was a problem connecting with the paypal gateway. (CODE)560022 The X-PAYPAL-APPLICATION-ID header contains an invalid value"

I have entered fully all the required advanced payment infomation

API Username (from paypal.com under selling tools)
API Password (from paypal.com under selling tools)
Signature (from paypal.com under selling tools)
Application ID from https://devportal.x.com

I have no idea what else i'm supposed to do, my paypal account type is already business. PLEASE HELP ME.