I had this problem and eventually got some good advice here so thanks to all who helped me.
No ammount of cleaning from inside helped at all.
To clarify what I did and hopefully help others with the same problem
Turned off electricity
Pulled out machine and turned upside down (remembered to remove dishes second time I did it)
Removed base plate with alan key and a bit of force
Found the location of the two filters/sensors that sit in the sump inside the machine
Twist off and removed the parts one looked like a suppository was’nt too bad but cleaned it up
Second was a round filter/sensor and full of gunge
Cleaned and replaced back the right way and in place tightly
Sucess