Apple acknowledges some MacBook and MacBook Pro laptops have faulty keyboards. The company published a list of MacBook models confirmed to be affected by these issues. Apple has offered free service to all affected customers. Users who encounter one of the issues can visit an Apple Store or authorized service and receive free service for their problems, even a full keyboard replacement, at no cost. Apple said users who in the past paid for their own repairs for the above-listed issues can also request a refund. The offer stands only for models listed above and for four years after the customer has bought his model at retail.
Source: https://www.bleepingcomputer.com/news/apple/apple-confirms-major-issues-with-macbook-keyboards-offers-free-service/