Use an accredited local e-bike service centre, e.g.:
adifferentgear (ADG) – see their servicing-and-repairs menu, accredited for Bosch, Shimano and Fazua systems.
JE James – (Bosch system and ?)
Tonybutterworths – (Bosch system and ?)
langsettcycles (Shimano system and ?)
Or go for a Mobile service
The good news is that DIY bearing repair kits and full refurbishment services are available from such as the highly recommended local firm that offers this service for many e-bike systems: https://www.peakbikemotorrepairs.com/ Chapel en le frith – Phone: 078880 29522.
Further afield https://www.ebikemotorcentre.com/ and https://www.e-motorrepairs.co.uk/services/ are available, so if you do have an (out of warranty) issue you don’t have to go to the expense of a complete new motor.