Can't activate pending order

I'm currently testing my website, and i have a mobilereseller to offer mobile webshops.

I installed the module correctly and all my data is correctly put in.

When i test order (or even a real order) I can't activate the pending order in whmcs admin. Even though the module is set to auto install after order.

It's a free demo so no payment is requered for the mobile webshop.

Any idea's how to fix this?

Thanks