Trouble with CE BJT amplifier
You wrote "All of them make use of 2n3904 for RF Amplifier".
But do they use it in the same way?

E.g. you are using a common emitter circuit but they may use e.g. a common base circuit.
The maximum frequency both circuits are able to amplify are quite different (i.e. much higher for common base).
In your case e.g. the Miller effect might be the problem.