2017 RX350 navigation update

[NATPISUPATI]

I have a 2017 rx 350 . Dealer tells me that Lexus has no updated chip to update the navigation . The latest version chip only goes to 2021. No after market chip is available due to Lexus proprietary chip technology. On my 2015 Camry I can get an after market chip and it works fine . Updated till 2023 . 
if Lexus has a proprietary chip and can’t provide an update and its their system we bought ( not cheap ) what are the legal ramifications to Lexus ? 
 

 

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