Q:

How to retrieve initial Db2 on Cloud password

Which is the initial password for the Db2 on Cloud profile? 
I'm trying to connect via DSM (Database Server Manager). 
IBMid and e-mail didn't work.  Where can I find the username and password? 

A:

You can obtain the username and password along with other connection information from the service credentials.  Go to the IBM Cloud dashboard, select the Db2 service and click on credentials.  If there are none yet, click on create. 
Another option is to bind the service to a Cloud Foundry app and to obtain the environment information.  There the credentials can also be seen.