pThumb on different contexts

[stream-7]

Hi,

I have my main website running on the 'web' context and a blog running on a 'blog' context.
pThumb created images show perfectly on the 'web' context but will not show on the 'blog' context pages.

The error log is as follows:
[2018-03-18 18:11:27] (ERROR @ /home/stream7/public_html/core/components/phpthumbof/model/phpthumbof.class.php : 156) [pThumb] Resource: 156 || Image: (none) [pThumb remote images] Failed to cache http://stream7.co.uk/assets/images/blog/2017.jpg

I'm guessing I need to add some Context settings to the 'blog' but I cannot find which settings to add.

Thanks,