Why are my Leads not Updating?

Hi, 

I have a lead that was created today (22-05-20T15.45). Our agent responded and scheduled an appointment (22-05-20T16:16)

When I navigate to the Leads section I can see the Lead was added on 22/05/20. I can see in the column "Days Since Last Communication" that an interaction took place "Less than an Hour". So far so good. 

I am making an HTTP request to v2/leads. I see created_at and updated_at. Why is updated_at not showing the timestamp when the agent contacted the lead? Because I did not find it in the documentation of v2/leads, is there a way to get "Days Since Last Communication" over a request? Any other work-around? 

Thanks for the help!