Format cells to Autosum time from exported report

Hi,
I need to format these cells to time and then autosum them from this exported report. I have tried custom formatting to hh:mm:ss and then autosum the cells (custom formatting the autosum cell) but I get a zero value. Please help.
thanks, Scott.

See the attached

Sorry still didn't work for me. When I try to formay the cells with that formula it still displays as 0:01:00 format and I can not autosum the cells.