Hoi @Snah68
Welkom op de klanten helpen klanten Community van Vodafone.
Do you have a subscription or prepaid? If you have prepaid you can just put it away and no longer use it. After 6 months, these will automatically expire if you do nothing with them.
If you have a subscription, you must cancel it via this website. Taking 1 month's notice into account! If you want to switch to another provider and take your numbers with you, you must NOT cancel them, but you must indicate to your new provider that you want to take the number from Vodafone to your new provider. More info see this page.