This has happened to me too. I have a Phev 2017 with the MMCS in south west London. After a short time either the signal to my preset station is lost or there's another glitch and it goes to Absolute 70s. All the preset names on DAB1-3 tabs are lost but the presets are still there under the '12E' '11A' etc labels. Choosing from the station list does NOT solve it. The scanning for stations fails intermittently. Whether I make a preset using station list or the tuning knob, it makes no difference. In the end, on every drive, my DAB station is lost and goes to Absolute 70s. This is highly frustrating and unacceptable for a car of this standard.
This started shortly after I had been rummaging under the passenger seat to find a lost coin but I can't imagine that could have caused it.