Best answer by Transparent
Simply send an email to them with the meter readings and Customer Services will update their database manually. The email method gives you a date/time stamp as proof of when you submitted the required information. The agent that replies will be able to advise on your options for paper statements, and paying on receipt of the bill. You might need to be on the variable tariff Simpler Energy, as all the fixed contracts require a Direct Debit.
Don't forget to provide them enough details to identify you with. If you know your account number, then give it, and in any case state your post-code. You should receive an email acknowledgement.
You should still be able to view your account status and enter meter readings online once your MyOVO page is fully active. This is unrelated to how you are paying.