Htek UC903

Back to Phone Model Examples
The phone provisioning is set using the Management top menu and then the Autoprovision left menu
The URL to enter is the simplest one, like 
https://demo.mirtapbx.com/mirtapbx/autoprovision/TBP96HnRhZxs7JbP/
In case your certificate is not accepted by the phone, it can be worth trying to allow any certificate or use not encrypted http