Unsurprisingly the flashing light is indicating a drainage fault.
There will be something jamming the pump.
Drain the water down again, unplug the appliance and take the filter out again.
Check to see if the impellor will "ping" around. Use a screwdriver to turn the impellor.
If it just rotates smoothly then the pump is broken.
If it pings round it's good.
If it doesn't turn, there's something in there.
If there is something in there and you can't get it out you'll need to take the pump out.
Tilt the machine back, if it has an open base, take out the screws holding the filter housing in place and then push it in to the machine and out the bottom. Disconnect the wiring and the hoses, take the pump out, clear it, refit it and reassemble the machine. Try again.
Hope this helps