Have you master reset?
How long did the process take?
Is your unit MY20 or later?.
Follow this guide as reference, it’s for NA but overall process should be similar → Tutorial: 2020 North America 2.20 Map Installation (Stand-Alone without Reformat) with Updated NAV_Voice 06/21/2021
As you can see, it’s quite a lengthy process with multiple reboots, and for EU should be about 2 hours or even more…