How can I change ringing timeout?

I use Asterisk 11 and try to change ringing timeout. It takes only 7~10 seconds to hangup automatically. I checked extension and it was like this.

extensions.conf (I use realtime database)
switch =>Realtime

Here is mysql database value in extensions table.

I changed this one to

However, there was no change. How can I extend ringing timeout to 60 seconds?

Have you reloaded the dialplan/database connection?
Show us a bit of your dialplan, according to the extensions you dial in this situation.

Seven seconds sounds like the SIP dialogue is faulting. You need to get better debugging information.