facing problems with inserting data

Then you need to troubleshoot and figure out why.
Trace the expected path of execution and find a way to test the expected inputs and outputs at each step.
For instance:
Is the ajax call requested url is correct? (IOW, is the right controller/method called?)
Are the expected parameters posted and are the values correct?
Do methods called in the controller get valid arguments and return a useful result?
Do the response headers of the ajax call have the expected contents?

One step at a time my friend.