Radio silence from customer service?

I’ve been with Bulb for a couple of months now for electricity only (gas is included in my rent). For seemingly no reason, my bill has gone from £35 to £70 for a small one bed flat with one occupant (myself). I’ve been trying to resolve this with customer service for weeks but I haven’t received a single thing back from them from various email addresses, web chats and Facebook. I can’t make phone calls and I’m at my wits end with my account now in a considerable amount of debt. I don’t know what else I can do except switch suppliers and dispute the debt.

Similarly having no response following the faulty installation of a SMETS2 meter. It seems commonplace due to the expansion of the business beyond their capacity (and wholly unacceptable).