I have a QMB Smart Signage monitor with Tizen 6.5. I can not use webapi and systemcontrlapi because of security error 18. Be noted that I add distributer certificate with partner level and add systemcontrol privilage to app.
What is the problem ?
I would suggest you sign in and open a Smart TV Seller Support Request . They can help you better there.
Samsung Developer Relations
I solve it by myself!
The problem was required_version at config.xml. I set 5.5 as required_version while I using APIs that mentioned “Since: 6.5” in developer site.