Sorry for reviving this!
It looks like the get_advertising doesn’t exist anymore, and I’m trying to send advertisement data, tried to search for it for multiple evenings and tried to find out how it all would work. This post seems to be the closest thing, except that it doesn’t compile anymore.
If anybody would could try to check if this is the case, and if there is an alternative, thanks!
[esp32_ble_server] Send advertisements with data - ESPHome - Home Assistant Community