Still waiting for prepayment electricity key

I changed to bulb about 6 weeks ago and received my prepayment gas card. That works fine. I’m still waiting for my prepayment electricity key. I’ve applied 3 times for this key and have neither received a response nor received the key. I don’t understand and feel quite disappointed about the service and lack of communication. My previous electricity supplier has already sent his last statement. Please send me the electricity key and get in touch about this.