Error You are not authorised to view this resource.

-- url of the page with the problem -- : www.elitetraining.co.uk/
-- HikaShop version -- : 3.2.2
-- Joomla version -- : 3.8.4
-- PHP version -- : 5.6
-- Browser(s) name and version -- : chrome 64.0.3282.140
-- Error-message(debug-mod must be tuned on) -- : none

Hi, I am getting this error message all of a sudden. The only thing I can remember doing over the last few days is upgrade Joomla to 3.8.4. this happens when you click add to cart from the games pages.

Any idea what is happening here?

Thanks

EDITED: Just updated to Joomla 3.8.5 and it is still an issue