!formatterError! on sat nav

Hi Everyone, new to the group and hoping someone could help me out.

I bought a Superb iv in 2020 (L&K) and a few months after getting it the MMI display locked and needed a code to "unlock it" as it thought it had been put in a different car!. The dealership said they replaced the head unit. After the replacement had been fitted I experienced multiple shut down and reboots of the MMI system, so went back to the dealer who said they would check the wiring  but couldnt find any problems.

I now not only have the random shut down/reboots, but also an intermittent error message !formatterError! on the sat nav when inputting a postcode. Sometimes it doesnt even allow any inputting of postcodes. The screen can also freeze.

In addition I have an intermittent problem where the display flashes up "SOS emergency call activated".

The dealer has now replaced the GPS aerial and amplifier but as it hasnt solved the issues is proposing to now replace the Emergency control module.

They are also intent on blaming my phone for the issues. (An Apple iphone 11 connected by bluetooth to Apple car play). I am not actually using the phone when these issues arise so struggle to see how this could be the cause.

As the dealership seem clueless and want to blame my phone, I wonder if anyone else has experience these problems and what the solution(s) might be.

Thanks