Cancelling mobile contract without calling

Hello,

I want to cancel my mobile contract with KPN. However, I do not want to call or be called on my phone because I am currently living abroad in the US. But I also don’t see why it’d even need to speak with somebody just to confirm that I indeed wish to cancel my contract. Honestly, I can't believe that something as simple as canceling a contract can't be done via a chat or online via a form - it almost feels like this is set up to make it more inconvenient for people to cancel their contracts.

My question is: is it possible to cancel the contract I have online, without having to talk to somebody.