I just bought a microwave (don't ask why )

Thing is the unit has the usual two-prong plug plus a long earth (grounding) wire.

The staff in the shop didn't convince me they had even a basic grasp of understanding what to do with it.

My house doesn't have any sockets with facility for connecting this earth wire.

What must I do with it ?

Can I just ignore that wire and use the microwave ?

Thanks in advance for any guidance