CF Pro Tools expert - Click funnels

I have the CF pro tools code and its set up in my funnel, it takes the paypal payment but is not getting back to the funnel upsell, i need that to work properly and that the upsell gets processed also. I know a fair bit about the code etc but i just cannot see where it's going wrong. Only apply if you know CF Pro tools and click funnels software I will provide video walk through to understand the job better thanks Mel