Restart RAS

Hi, our company uses ISDN dial up with RAS.Every few days I have to restart
the RAS service as it shows busy when I dial the server modem.
I changed the modem and still no change.
For diagnostics purposesI connected to modem using Hterm and could see RING
RING which proved the modem was fine.
When I switched back to RAS, still no joy.Only after resetting RAS servive,
then I can dial in several timer over 2-3 days, then the same problem repeats
itself.

Any suggestions? or does anyone know how to write a scheduled script to
restart the RAS service daily