Hi Afreen,
This forum is a collaborative one and can't replace support (https://www.appdynamics.com/support/). So we do our best to help you as soon as we can.
Can you give us a bit more context to what you are trying to do?
Do you have a Java or .Net or any other AppServer agent on the same instance?
Have you checked if your agent reports correctly (settings button on the upper right corner then AppDynamics agent)?
You can also check machine agent log file (machineagentinstalldir/log/machineagent.log file).
Thanks
JB