Conflict of conscience!!!

Hello, everyone now knows that it is forbidden in Germany to use a mobile phone at the wheel of a vehicle (with running engine). About half an hour ago I was in a situation where I cursed this law. I drove on the highway and approached a foreign vehicle with trailer, which was absolutely not illuminated. Probably the plug of the trailer was not connected at all. The trailer was also so wide and high that it was the Beleuc As this is a threat to starvation traffic, you should normally inform the police in this case. But now it comes: It is forbidden to make a phone call during the journey! And since I don’t want to get a point in Flensburg, I don’t have that, of course. Now, of course, I’m interested in whether there are certain exceptions that allow me to make phone calls while travelling without being prosecuted? And are these exceptions legally defined or is this an interpretative matter of the situation? Greeting Tiboron