How to enable redirAfter : 600000  ( 10 mins) & warn after : 1200000 (20 mins)

I have requirement to enable bootstrap modal pop up to show warn pop up at 20 minutes and redirect , redirect count down start from 10 mins to 0. I tried changing these values  warnAfter: 120000,   redirAfter: 60000, but  pop up not showing up. Could I please get some guidance on this.




Thanks,
Srini 