Hello,
Thank you for your question
To purchase the Top Up's please contact your sales manager.
If you want detailed instructions, how to Top Up the SIM card using IoT platform, please reach us via VIP helpdesk and we will send detailed instructions how to create Top Up rules so your SIM cards Top Up automatically when the data amount reaches dedicated value and how to Top Up SIM cards manually.
Also you can find useful information on the IoT portal here - https://docs.things.truphone.com/docs/iot-portal/overview/
Can you clarify what do you mean by "cancel this card"?
Regards
