Projects -> New -> Traffic management -> traffic condition.
This will create a new tab under traffic management. Then you can specify the type of incident e.g., lane blockage, closure, speed change etc., with the ability to specify the duration, lane, location, length etc.
Once you provide this specification, go to your scenario (static, dynamic etc. the one you are working on ), and the 5th tab named strategies and conditions will now show you an option to add the incident you created in the previous step. Run the simulation, and it considers your desired effect.