Double billed and poor service

My contract with rain is fairly new. Got the wifi unit end of April and waited for them to debit on 01/05/2024, even checked on my account on 01/05/2034 but there was no bill for me to pay and the balance was on R0.00. To my surprise I get a bill for May and June combined, mined you there was no intention/notification of a debit in May. How is this fair that I have to pay so much money and how is it my fault that my account was never debited in May?? We work on budgets every month and the economy is tough. Called in this morning after being on hold for more than 10mins and the agent could not even explain why I was never debited for May and that I have to pay the full bill of R1113. I didn't agree with he said and then rather told him that rain should bill me for May, cancel my account with Rain and come collect their wifi unit. Agent was then very quick to transfer the call to the cancelation department but got put on hold again until the call cut. Your service and the way you treat your clients is really pathetic and unprofessional!! Can I please get this sorted ASAP so I pay my bill for May and cancel my account.