Survey users get 403 access to page is forbidden

Hi,

I've recently updated to Community Surveys 6.4.2 and notice that my users now get 403 error when responding to surveys.

I've ensured that the permissions allow public to respond to surveys and view results (screenshots attached).

I've cleared Joomla and hosting control panel cache. Done the shift or ctrl + refresh on browser. No change.

What am I missing?

Thanks,

Ari