Cannot install ruby version 2.6.6 on Ubuntu 20.04

[Tenish14]

I have an existing project which is using ruby version 2.6.6. But my machine ruby version is 3.0.2. So when I try to run my project on my machine it shows this error.

Your Ruby version is 3.0.2, but your Gemfile specified 2.6.6

So I also try to install ruby 2.6.6 using rbenv environment

rbenv install 2.6.6
Installing ruby-2.6.6...

BUILD FAILED (Ubuntu 22.04 using ruby-build 20220426)

Inspect or clean up the working tree at /tmp/ruby-build.20220501122810.9309.e7yCPU
Results logged to /tmp/ruby-build.20220501122810.9309.log

Last 10 log lines:
installing default date_core libraries
linking shared-object fiddle.so
make[2]: Leaving directory '/tmp/ruby-build.20220501122810.9309.e7yCPU/ruby-2.6.6/ext/readline'
make[2]: Leaving directory '/tmp/ruby-build.20220501122810.9309.e7yCPU/ruby-2.6.6/ext/fiddle'
linking shared-object bigdecimal.so
make[2]: Leaving directory '/tmp/ruby-build.20220501122810.9309.e7yCPU/ruby-2.6.6/ext/bigdecimal'
linking shared-object date_core.so
make[2]: Leaving directory '/tmp/ruby-build.20220501122810.9309.e7yCPU/ruby-2.6.6/ext/date'
make[1]: Leaving directory '/tmp/ruby-build.20220501122810.9309.e7yCPU/ruby-2.6.6'
make: *** [uncommon.mk:286: build-ext] Error 2

So I not sure how to make it work. Anybody can help with this. I try all the possible way from the internet but it doesnt work.

ruby -v
ruby 3.0.2p107 (2021-07-07 revision 0db68f0233) [x86_64-linux-gnu]

Rails -v
Rails 6.1.4.1

Rbenv --version
rbenv 1.1.2

Ruby-build log file link: https://gist.github.com/Tenish14/6bafdf4605e0a1be5b611f9ff7aff2f6

[mislav]

Ruby-build log file link: https://gist.github.com/Tenish14/6bafdf4605e0a1be5b611f9ff7aff2f6

Please note that the contents under this link isn't a log file, but the source of the ruby-build binary. Without the log file, it will be hard for anyone to understand what happened during your build, since the last 10 log lines you pasted don't contain useful information.

You could try the instructions provided here #1940 (comment)