Unlocking an old contract phone

[Bevelrly]

I have an old phone that was on contract to Vodafone (since upgraded with them). I want to unlock the old phone so that my mother can use it.  I went online to use their unlocking form but Im worried that they will unlock my current phone.  I did have to put the long number onto the form from the back of the old phone but didnt want to jinx anything.  Can anyone advice please.  I cant speak to anyone at Vodafone

[BandOfBrothers]

They will unlock the phone that you've entered the imei number for @Bevelrly 

[Bevelrly]

Thank you