Additional information:
The voucher has to be used this year (2022), or it can be used next year if the reservation is in 2022.
Norwegian says this: "it is possible to make a booking for someone else, as our terms & conditions don't demand that you spend your CashPoints on yourself as the traveler(s).
Your CashPoints are valid until 31.12.2022, but you can use your CashPoints for flights in 2023, as long as the reservation is done before the end of 2022."