*My development environment is Ubuntu15.10 and x86_64.
I need ngrok version2 Linux64-Bit!!
I searched how to ngrok version up. Example, once remove ngrok and reinstall ngrok. Example, command "ngrok update". Example, I watched ngrok help command. But I could not solve this problem.
Do you know anything to solve?
I asked for advice on alan who is developing ngrok.
With alan's advice and a little search, I could solve this problem. There were two causes.
First cause, Alan said that "delete ngrok from your system before downloading the new version". I was planning to delete it just by putting it in the trash can. It was completely disappeared by command line($sudo apt-get remove ngrok-client).
Second cause, I downloaded ngrok by command line($sudo apt-get install ngrok-client) on terminal. Ubuntu15.05. Ubuntu seems to be able to download only up to version 1.6(https://www.howtoinstall.co/en/ubuntu/trusty/ngrok-client). Even if I erased it repeatedly, it was only version 1.6($sudo apt-get install ngrok-client & sudo apt-get remove ngrok-client). But manual downloading worked by this page(https://ngrok.com/download), I downloaded version2.1.18.
I was able to solve this problem. Thank you Alan!!!