Ok that light flashing is the error code for a water inlet fault.
What you need to do is just make sure the water is turned on for the dishwasher.
If that's ok then what you need to do is pull the dishwasher out and remove the water hose from the back.
Make sure its unplugged and remove the plastic cover just behind were the water hose goes to.
From there pull the water valve out a bit and pull the clear thin hose off the valve on the top.
Then look inside were the valve goes and you will see a red hose. Pull the end cap of this and drain any water away that's in there.
Then refit the cap and refit the hose onto the valve and refit the covers and fill hose.
Now retry the dishwasher and fingers crossed this will cure the fault and get it up and running again.
If not then the IWMS on the left hand side will need to be replaced. This is the water metering tank.
But try the above first as most of the time this cures it.