Hi Manmohan,
Please follow below options :
1.Either use Single Sign-On option
2.If your team members are using any common shared portal ,please create one link inside that for maintaining SAP System username & password (make everyone aware about that ).Moreover put your team members in alert mode against that link so in case if anyone is changing password you get a automated mail about the changes made in password for any of those system .
3.
a)If all the users are locked then, login to Database access the table USR02 and delete the entry of SAP* of specific Client and then logn to SAP to that particular client by using password pass.
b)Unlock in the SU01 t-code if you have other userid for Ides.
I hope anyone of the steps mentioned above will resolve your query .
Best Regards,
Praveen Srivastava