How to fix git version bump gem error on windows 7

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Ruby

Sinatra

When I tried to run my Sinatra app, I got this error:

C:\Users\A2\Desktop\freetouring_v2>rackup -p 4444
The system cannot find the path specified.
The system cannot find the path specified.
The system cannot find the path specified.
C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/git-version-bump-0.15.1/lib/git-version-b
ump.rb:299:in `gem_version': GVB.version(false) failed; perhaps you need to inst
all git? (GitVersionBump::VersionUnobtainable)
from C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/git-version-bump-0.15.1/lib/
git-version-bump.rb:37:in `version'
from C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/git-version-bump-0.15.1/lib/
git-version-bump/version.rb:2:in `<module:gitversionbump xmlns:module="#unknown">'
from C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/git-version-bump-0.15.1/lib/
git-version-bump/version.rb:1:in `<top>'
from C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/backports-3.6.7/lib/backport
s/std_lib.rb:9:in `require'

I have Git in my %PATH%. This is echo of my %PATH%:

C:\ProgramData\Oracle\Java\javapath;C:\Ruby22-x64\bin;C:\Windows\system32;C:\Win
dows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Pro
gram Files (x86)\Skype\Phone\;C:\Program Files\Git\bin\;C:\Program Files\Git\cmd
\;C:\Program Files (x86)\Microsoft VS Code\bin

So, can anyone explain to me where exactly is the problem and how to solve it?
Thanks in advance.

What I have tried:

I didn't found any other solution except to set Git in my PATH, did that, but I keep getting the same error.