How old is your 12V battery in the trunk?
I was going to suggest replacing the 12V battery or have it tested for free at a store. That seems to be everyone's first suggestion when it's related to something electrical.My car is 2017, hasn't been replaced since.
I would call them before you show up. Here in the USA, you can go to an Autozone or Advance Auto, I think Walmart even, etc. (and some other local non chain shops) and they won't charge to do a battery test.No, so if I remove battery and take it to a shop they should be able to provide me a free battery check?