Hello Chris,
Marcio hasn’t returned to the forum since he posted this, so we are none the wiser.
My questions would be:- have you too changed the reservoir and sensor? If so, genuine VAG parts?
If not, I would be first arming myself with a spray of contact cleaner, and disconnecting the plug at the base of the reservoir - the plug connecting to the level sensor. Examine the condition of the contacts, if there is any corrosion present then remove as much as possible before applying a good squirt of contact cleaner - then wiggle the plug.
If this doesn’t sort it, then you will need to renew the sensor.
Kind regards,
Gareth.