When I open up the dashboard after installing Horton works HDP platform. I get 27 alerts. I do now know why? I have included a picture!
Looks like many of your services are not fully running like YARN/MapReduce/Kafka/Zookeeper ...etc
So that will lead to Alerts because ambari will keep tracking the status of those components.
So in order to get those alerts fixed better to start those services successfully and then after that those alerts should get cleared in next execution of alerting scripts.
As you are running Sandbox which has many services installed, hence it would be good to stop the services which you are not using currently and put them in maintenance mode (means no alert will be triggered for the services which are in maintenance mode).
By keeping the services which you are actually using will help in reducing the Memory/Resource utilisation of the Sandbox Host.