Welcome to Vodafone Community
I emailed Vodafone last week to request that my iPhone be unlocked, I received an email a few days later saying I am nearly there and to put a non Vodafone sim into my device to complete the process. When I try this my device tells me the Sim is not supported. Is there something elase I need to do?
That email can certainly be confusing, it means Vodafone have sent the requst to Apple and are waiting for Apple to unlock the phone on Apple database.
Just keep trting the alternative SIM in the phone, when Apple have completed the unlocking, you will get a message on the screen to the effect.
Please see this previous thread: https://forum.vodafone.co.uk/t5/Unlocking/Unlock-Iphone-7/td-p/2633413