Need help settling with Cashland - anyone had luck?

I currently am in default on a payday loan with Cashland (storefront)and I will call them to try to work out payment arrangements tomorrow. My problem is that I have already agreed to 3 extended Pymt plans (EPP) w/ other storefronts totaling $700 per paycheck and does not leave much to pay my other bills and cashladn . I left a message with the collection person who called me today and asked if I could pay back $150 every two weeks until paid and she called back saying her supervisor said that would not work but that she could work out arrangements with me. I will call her tomorrow to try to work something out. Has anyone had any luck in paying them back over a longer period of time? I would be interested to hear what your approach was if you were successful....thanks for any help ...I am nervous :O