Tunze Osmolator 3155

[Blue Ram]

I've been having issues with this for the last couple of months in that the operating sensor does not have contact with the water level and the pump is not turning on to top up to the level set. The unit was put in my sump last May and for the last couple of months, it has not been functioning correctly or consistently. I have tried all of the trouble-shooting tips in the manual already.
This week I raised the issue with the manufacturer as it is still under warranty. This is the response I received -

"Remove any magnetic fields or object suspectible to create a magnetic field close to the 5017 control unit. Usually solves the issue right away".

I'm not sure what would cause a magnetic field?

I was able to get the unit to top up to the level set last night by moving some of the controller cables around so they are not in contact with any other electrical cables but this morning the water level had dropped again and was not topped up.

Anyone have any other suggestions or can clarify what the rep advised?
I will be following up with them again for clarification as well.