How to get Cortana enabled back on my Lumia 620 ?

[Windows Central Question]

Since the first update to windows 8.1, I can enable Cortana easily even though I am out of region. Cortana works very well and I was amazed and love it. However, after the denim update Cortana wouldn't respond to my command to sing , joke ,and didn't answer my questions. Instead, it shows what it get from the web on the screen. As for that, I was very disappointed and deleted the record of me and uninstall it.. And now I want Cortana back. But even though I've change the language and region settings to Unites States, Cortana did not appear at all in the setting nor in the apps list. How to install it back?

 

[colinkiama]

Go to the settings, swipe sideways to applications, tap in Cortana and turn the switch on