Unfair trading practices

I have a pre fitted SIM to allow access as a hotspot and to communicate with Lexus 'My Connected Services'. The free trial has now ended and find I can only purchase an exorbitant subscription to Orange. I cannot replace the card with one more suitable to my needs - less expensive. Are Lexus allowed to force me to take out a subscription so they can have another revenue stream? My previous Jaguars all had interchangeable SIMS.