Hello to everyone, I am trying to perform a very easy simulation: a copper bar with fixed current, wich is the value of joule losses? Wich is the distribution of the temperature after 10 s?

To do that I set a "Steady state AC Magnetic coupled with Transient Thermal", I created a circuit (here below) with just a solid conductor, a current generator and the ground.

I associated the solid conductors terminals to the two small surfaces. I set the lateral regions like this: Normal magnetic Field (tangential ELECTRIC filed).
After I solve the scenario, the check Physics is ok but I get this error:

Any clue of the reason? Thank you
Gianluca