C30 1.6 drive complete cut out of engine

[Sqwin1971]

Hi can anyone help please!!
I have a 2010 C30 1.6 drive. Several times on the A1 my car has totally cut out whilst driving. No power no lights or hazard lights. Reduced engine performance on dash. States turn key off. It takes over a minute to wait until car turn back on. It's very frightening. Any ideas???? Booked I to volvo next week

Thanks