Error with VS Test Assembly task on Azure Devops Pipeline

Hi all,

I need your help in resolving an issue I am having when integrating automated test in my azure pipeline. I am usng Vs Test assembly to run my test but unfortunately the tests are not running at all due to error in the path. I am getting and error like so: 

##[error]TypeError: Path must be a string. Received null

 

I have set up the task following the tesk complete documentation but not sure if I've missed something or not. Below is what the setup looks like:

Also, do I need to include command line script in running the test on my build server?

 

Thank you in advance for your much appreciated response