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Google Fi giving out gifts for Black Friday has basically become an annual tradition. In past years, they have offered Google Play gift cards, Google phones (with the purchase amount eligible to be exchanged for select gift cards), and free Google Fi service. This year’s offer is 1 free year of YouTube Premium. You can see it both in the email and in the Fi interface, but here’s the catch: you need to switch to an unlimited plan in order to claim it.
If you didn’t receive the email, check your account instead.
It also works for existing Premium subscribers by adding 1 extra year. If you do not want it to renew, you’ll need to contact customer service via chat to cancel.