Unlocking an iPhone 5 that has not been used for a year

[jesterward]

Hi

As a family we have been with Vodafone for nearly 10 years on pay monthly deals.

We have a spare iPhone 5s that we wish to unlock. My daughter used it (with her current Vodafone number) up until last January (when she got an iPhone 7 and just swapped out the sim card) and the iphone 5s has been sitting in a drawer unused since then.  

We want to give the phone to my elderly mother (who is with another network) so we need to unlock it.

As the phone has not been used for a year can I still apply using the NUC form giving my daughters current phone number as the one last used by the phone, or is there a different process?

Many thanks in advance

[BandOfBrothers]

You could try filling out the Nuc Unlocking form using the last account and.number details used in it but if the iPhone's imei number has dropped off then it would be a case of using a Payg SIM card in the phone for 30 days making calls etc and then use the new Payg details to request its unlock or use someone's contract Vodafone sim in it that have had it running for more than x3 bills paid on time, again making calls etc for a few days and then request the unlock using those details.