Error while loading student info

While logged in as an administrator, the result output works fine in the page. But when logged out or for visitors, it doesn’t work. it says “<!DOCTY” in every field.

Please help with this issue as we need this result portal to be available publicly (not only for logged in users.) Please go to https://www.cieglobal.co.uk/verification/ and use ULN 1234567890

Thanks.

https://www.ads-software.com/plugins/simple-student-result/