How can I disable home page and dashboard default option in destination tab in agent in OBIEE 12c

User_ER9S8

The problem is when we create agent, by default the homepage and dashboard option is checked and this gives out an alert for each agent on the homepage of the recipient( this creates 100s of alerts for one user ). We want to disable this. There must be some configuration file where the default setting are configured for agent/ibots in obiee or I am thinking we need to go into analytics/res to get the JS file in which that is invoke?

Using obiee 12.2.1.4

Please help.