Hi, I know you guys aren't plugin support but this is where I'd get the most relevant and fastest response. For some reason my thank you system addon shows twice. How do I fix this?
Check your postbit/postbit_classic templates for duplicated variables.
Basically what Shade means is ->
Go to Admin CP -> Templates And Styles > Templates > Theme Templates > Postbit > postbit
Find variables such as {$lang->tyl_given}(this will be duplicate) and remove them.
Check the template for more variables like this and it will be fixed
Make a backup of template before you modify.