Ford Figo wheel inner liners fall off

On my 8 month old 2014 Ford Figo the wheel liners came loose, and was taken to BB Ford Menlyn for corrective action. They merely popped the liners back with the same plastic plugs. 2 months later, both of the rear inner liners are missing. They refuse to replace, since \we do not cover missing parts". Do they really expect a person to stop on the highway (at night) and collect pieces of inner liners that were ill fitted in the first place? The vehicle was with them for exactly the same problem"