SQL1092N "" does not have the authority to perform the requested

First you need to make sure do you have SYSADM_GROUP setup

get dbm cfg

Probably you may want to update your SYSADM_GROUP to one of your Security group.
The command will be like this

update dbm cfg SYSADM_GROUP DB2ADMIN

http://publib.boulder.ibm.com/infocenter/db2v7luw/index.jsp?topic=/com.ibm.db2v7.doc/db2c4/db2c458.htm

If you are using Windows make sure you add your user Id back to the group of DB2ADMIN.

After that do a DB2STOP and START and retry your operation again.