unable to fetch session id from SFDC

Dear Experts,

I am working on Idoc to soap (SFDC) scenario.When fetching the session ID using lookup from webservice we are unable to fetch.

it was an existing scenario which was working correctly, We have done a password change and after changing the password we are not able to get the session ID.

We have done the same password change in DEV environment it is working correctly but not in QA.

Could you suggest...

Thanks,

Suma.