Could not find gem 'sqlite (= 1.3.11)'

Hello guys! I’m studying Rails and I’m still a newbie, I was following a
tutorial and everything was going smoothly, but then, when I tried to
run the following command line:

$ rails server -b $IP -p $PORT

it said that it was unable to find puma, and it told me that i should
run ‘bundle install’ first.

When I run ‘bundle install’, it gives me the following error:

Could not find gem ‘sqlite (= 1.3.11)’ in any of the gem sources listed in your
Gemfile or available on this machine.

If I run ‘$gem install sqlite3’, I get the following message:

Successfully installed sqlite3-1.3.11
1 gem installed

But I still can’t run ‘bundle install’, as it keeps telling me that it
can’t find sqlite!

I’m using cloud9 and Rails

Help, please?