I tried to call to change my banking details but the phone number is not working

I tried to call to change my banking details but the phone number is not working. I then tried the whatsapp number on their website but there are no options for changing banking details. It is so difficult these days just to speak to someone working at any company, but when you ow them money then you are called immediately. If I have a problem then I want to speak to a person not a chatbot.