fnd_global.apps_initialize not working

Below code has been used in the concurrent program(stored procedure). However after this call the concurrent program process not going further and it stops there only. Why this happen? The values of user id, resp id, app id are getting printed before however not printed after in the log file. why?

below CODE (from stored procedure)

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    debug('fnd_global.user_id       : ' ||fnd_global.user_id);

    debug('fnd_global.resp_id       : ' ||fnd_global.resp_id);

    debug('fnd_global.resp_appl_id  : ' ||fnd_global.resp_appl_id);

   

     fnd_global.apps_initialize(fnd_global.user_id

                             , fnd_global.resp_id