In this video:

In the dashboard course you have learned that you can find alerts on the dashboard that indicate operational or technical issues that need to be resolved:

You can also find these alerts on the planning screen:

Vehicle related alerts

These are alerts related to the vehicle. These appear in the resource column.

A few examples are:

Contract alerts

There are also alerts on the contracts that give the contract a red or orange line.

When you hover on the contract, you'll see the details. 

Here are some examples of contract alerts:

Automatic extension of the contract in case of a late check-in

When a resource is late for check-in, the contract will be extended automatically. 

In the planning you'll see that the contract is marked with a red line.  

Until the resource has returned to the fleet, you will keep seeing the contract in the planning.