Thank you for your quick response.
As u mentioned I have checked *.out file, MODFLOW did not get terminated successfully.
Last line of the output file is " SOLUTION DIDNOT CONVERGE FOR HEADS ".
While checking the simulation I have encountered with the error " Starting heads lower than bottom elevation" . I have solved that error by making IBOUND values inactive for those cells. Now there are no errors after I run "check simulation".
I used PCG solver, increased iterations to 100, 500 and 1000. But every time it ends up giving the same error.
Mapping of data (elevation